Glossary: what changed

Revision 1 to 2. Removed lines have a minus sign; added lines have a plus sign.

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1	1		This page will never be complete. You are encouraged to continue adding things to it that —
2	2
3	3		- Relate to this site
4	4		- Relate to Free Pascal
5	5		- Relate to Lazarus
6	6
7	7		Note that the [[buildfaq]] also has a FPC/Lazarus glossary
8	8
9	9		\| \|
10	10		\|:--:\|
11		-	~~\| <span style="font-size:16pt"># A B C D E F G H I J K L M N O P Q R S T U V W X Y Z</span> \|~~
	11	+	\| # A B C D E F G H I J K L M N O P Q R S T U V W X Y Z \|
12	12		\| \|
13	13
14	14		## \#
15	15
16	16		## A
17	17
18	18		### Ada
19	19
20	20		Computer language derived from Pascal and Modula, and named after Charles Babbage's lady friend. Babbage (1791–1871), an Englishman, was one of the earliest exponents of computer design and published a design for a "difference engine" (which he never actually built). Ada King, Countess of Lovelace and daughter of the poet Lord Byron, was a student/colleague of Babbage and wrote a program to drive the difference engine; she can be regarded as the first computer programmer. (There was no romantic involvement with Babbage.)
21	21
22	22		Ada is a high-level procedural language, with very similar structure and syntax to Pascal, but with several extensions. At one time in the 1980s, the U.S. Department of Defense decreed that all programming by its contractors must be done using Ada, but unfortunately there was a dearth of suitable compilers and software development tools, and the language never achieved popularity. Very few applications for the U.S. military were actually written in Ada.
23	23
24	24		### Assembler, Assembly Language
25	25
26	26		An assembler converts human-readable symbols (that represent machine instructions) into the actual binary instructions that the computer executes. For example an assembler would translate
27	27
28	28		`LD a,b # move the contents of location a into location b`
29	29
30	30		into a binary sequence such as `01110010` which the machine can execute. Assembly language is the list of codified instructions that a programmer writes, which the assembler translates into machine code.
31	31
32	32		An assembler differs from a [[Glossary\|Compiler]] by being processor-specific (i.e., different assemblers for i386, MC68000, ARM processors, etc.) and by being much more low-level: it deals with very specific instructions to move data and perform detailed arithmetic. Many compilers (including [[Glossary\|Free Pascal]]) allow the programmer to embed Assembler sections within the high-level source code; such sections are, of course, only useful using the processor for which they are intended, whereas a [[Glossary\|Compiler]] can write programs which will work on a variety of different processors.
33	33
34	34		### API
35	35
36	36		Application Program Interface: a set of tools such as procedural/functional calls to allow programmers to use a software package.
37	37
38	38		An example is the API for the [MySQL](http://www.mysql.com) database system; its authors have published a set of definitions for procedure/function calls, with detailed specifications for each of the parameters or arguments for each function. The original MySQL API was defined for [[Glossary\|C]] programming, but the Free Pascal developers have written a set of corresponding procedure/function call definitions which allow [[Glossary\|Free Pascal]] or [[Glossary\|Lazarus]] programmers to use the library of MySQL function calls.
39	39
40	40		A very important part of any API is its documentation, and any conversion of an API library to a different programming environment (e.g., from C to Free Pascal) requires a really excellent set of descriptive documents.
41	41
42	42		## B
43	43
44	44		### BASIC
45	45
46	46		BASIC is an acronym that stands for Beginner's All-purpose Symbolic Instruction Code.
47	47
48	48		A computer language once popular as a training tool, or as an experimental tool for programming, it was developed in 1963–1964 at Dartmouth College in Hanover, New Hampshire, U.S.A. by professors John G. Kemeny and Thomas E. Kurtz. The original version of BASIC was a compiled language and quite efficient on the slow computers of the early 1960s; however, a majority of people were first introduced to pared-down [[Glossary\|interpreted]] versions, particularly those that ran on early microcomputers, and they did not support many of the language features of Dartmouth BASIC. Whether the version in use was compiled or interpreted, it was easy and quick to make changes in one's program and see the effects. The programmer gave a line number for each statement, and the sequence of execution was determined by the order of line numbers. Extra lines could be inserted by giving them intermediate line numbers, e.g., line 15 could be inserted between lines 10 and 20. The original language required the use of line numbers for every line of code. Execution could be transferred by using `GOTO <line number>`, and it was possible to develop very undisciplined habits by the uncontrolled use of GOTOs; the result was sometimes called "spaghetti code". In many ways early BASIC was the exact antithesis of [[Glossary\|Pascal]] with its strong emphasis on structured programming. However, even as inferior BASIC interpreters proliferated on personal computers, BASIC kept evolving at Dartmouth College and elsewhere, and eventually the need for line numbers and GOTO statements was dropped, allowing it to be used for structured programming. One modern commercial variant, for example, is True BASIC, which conforms to ANSI Standard BASIC. It allows programs to be compiled and bound to a runtime module so that they can be run independently of the development environment and compiler.
49	49
50	50		BASIC has latterly fallen out of favour, partly because of the introduction of languages like [[Glossary\|Pascal]] and [[Glossary\|C]], and partly because of the huge improvement in speed of computers and performance of compilers so that proper compiled programs could rapidly be written, executed and debugged. There have been some attempts to improve upon BASIC, such as Microsoft's Visual Basic — which supports some rudimentary structures and doesn't use line numbers, so there is less emphasis on GOTOs — but these latter variants are almost unrecognisable as BASIC, and owe much to C and to several [[Glossary\|Command Line]] or scripting languages. In fact, some Visual Basic programs may look very similar to [[Glossary\|Free Pascal]] or [[Glossary\|Lazarus]] programs.
51	51
52	52		For more information on the origins and evolution of BASIC, see Back to BASIC, by John G. Kemeny and Thomas E. Kurtz (Addison-Wesley Publishing Co., 1985 ISBN 0-201-13433-0).
53	53
54	54		### BOM
55	55
56	56		The byte order mark (BOM) is a particular usage of the special Unicode character, U+FEFF, whose appearance as a magic number at the start of a text stream can signal several things to a program reading the text:
57	57
58	58		- The byte order, or endianness, of the text stream in the cases of 16-bit and 32-bit encodings;
59	59		- The fact that the text stream's encoding is Unicode, to a high level of confidence;
60	60		- Which Unicode character encoding is used.
61	61
62	62		BOM use is optional. Its presence interferes with the use of UTF-8 by software that does not expect non-ASCII bytes at the start of a file but that could otherwise handle the text stream.
63	63
64	64		### [[Boolean]]
65	65
66	66		Logical data type in [[Glossary\|Pascal]] and other languages that can take one of two values, [[True]] or [[False]].
67	67
68	68		Named after George Boole, a pioneer of logical (Boolean) Algebra.
69	69
70	70		See [[Boolean Expressions]] for a full description.
71	71
72	72		### Bug
73	73
74	74		An error in a program which might cause catastrophic machine failure, failure of the program or simply incorrect performance or output. Derived from the days when computers were constructed with thermionic vacuum tubes: insects (bugs) crawling around the interior of the apparatus could cause short-circuits between terminals producing hardware failure or unpredictable performance.
75	75
76	76		Most software development teams encourage potential users to report bugs (which are then corrected in subsequent versions) and have a clearly-defined bug-reporting mechanism (for example Lazarus [BugTracker](http://bugs.freepascal.org/main_page.php)).
77	77
78	78		## C
79	79
80	80		### C programming language
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82	82		A widely used computer programming language, particularly useful for system programming. Forms the basis for most of the [[Glossary\|Linux]] operating system, and as far as we can determine, for the [[Glossary\|Windows]] system. Its chief disadvantage is that it is insufficiently rigorous, and allows poor programming practices to creep in. It is also vulnerable to problems such as memory leaks and buffer overflows. By contrast, [[Glossary\|Pascal]] imposes a much more rigorous discipline on the programmer and encourages good programming habits and practices.
83	83
84	84		See also [[Pascal for C users]]
85	85
86	86		### C++
87	87
88	88		A variant of [[Glossary\|C]] which includes Object-Oriented Programming constructs.
89	89
90	90		### C#
91	91
92	92		Pronounced "C-sharp", a language heavily supported by Microsoft and designed for their .NET platform. It has a syntax based on [[Glossary\|C++]] that includes aspects of other programming languages, most notably Object [[Glossary\|Pascal]] and [[Glossary\|Java]].
93	93
94	94		### CCR
95	95
96	96		Code and Component Repository
97	97
98	98		The [Lazarus Code & Component Repository](http://lazarus-ccr.sourceforge.net/) on SourceForge is the host for the Lazarus Documentation files and some component libraries.
99	99
100	100		### Class
101	101
102	102		A special kind of [[Glossary\|Object]] in [[Glossary\|Object Oriented]] programming.
103	103
104	104		A Class is a pointer to an Object; its declaration looks very similar to an Object.
105	105
106	106		### COBOL
107	107
108	108		COmmercial and Business Oriented Language
109	109
110	110		A language widely used in business in the 1960s and later. Despite its deficiencies, and the introduction of newer languages, it is still in widespread use, mainly as a legacy system. The most notable recent \[<http://www.theregister.co.uk/2008/08/14/cobol_california/%5Dexample> is in the State of California, where the government payroll system still uses COBOL, and the governor's recent edict that state employees' salaries should be cut has run into difficulties, because there aren't enough COBOL programmers around!
111	111
112	112		### Command Line Interpreter
113	113
114	114		CLI
115	115
116	116		A program present in most computer operating systems which examines an input stream, either from the keyboard (Console Mode) or from a text file (Batch Mode), [[Glossary\|interpreting]] or parsing the text to find instructions causing execution of operating system commands or running prepared programs or other scripts of instructions.
117	117
118	118		The CLI environment, where the operator types commands on a keyboard at a console, exists in contrast to the [[Glossary\|Graphical User Interface]] (GUI), where the operator makes more use of a mouse, and pictures rather than text convey information to the operator.
119	119
120	120		### Compiler
121	121
122	122		A program that translates Human-readable source code, usually written in a high-level language such as Object [[Glossary\|Pascal]], [[Glossary\|C++]], Algol, [[Glossary\|FORTRAN]] or [[Glossary\|Ada]], into machine instructions for execution by a computer.
123	123
124	124		Compilation usually involves several stages: Parsing the source code to check for syntax errors, translation of the source code to machine instructions, and [[Glossary\|linking]] the resultant code with libraries in order to produce the final machine-executable application.
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126	126		See also [[Compiler]] and [[Compilers]] entries in main Wiki.
127	127
128	128		### Component
129	129
130	130		A small piece of code, typically consisting of a data definition or a small number of methods, which defines and describes a particular action or series of actions in a Pascal application. Components are typically grouped together functionally into libraries such as the [[Glossary\|Free Pascal Component Library (FCL)]], [[Glossary\|Lazarus Component Library (LCL)]] or [[Glossary\|Run Time Library (RTL)]], so that they can be re-used in many programming applications.
131	131
132	132		### Cross Compilation
133	133
134	134		The act of compiling a program on one type of computer for eventual use on another computer with a different processor a different operating system. For example [[Glossary\|Pascal]] programs can be cross-compiled on a PC running Linux and executed on a PC running [[Glossary\|Windows]], or programs can be compiled on a PC to run on a [[Glossary\|PDA]] like the Sharp [[Glossary\|Zaurus]] or devices using [[Glossary\|WinCE]].
135	135
136	136		Another typical example is the Cross-compilation of the [[Glossary\|Free Pascal]] Compiler or the [[Glossary\|Lazarus]] IDE on one platform such as [[Glossary\|Linux]] for use on another platform such as [[Glossary\|Windows]] or on the [[Glossary\|Macintosh]] computer using a totally different processor.
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138	138		### Cross-platform
139	139
140	140		Usually refers to a program that can be run on several different [[Glossary\|Operating Systems]] and Platforms such as [[Glossary\|Windows]], [[Glossary\|Linux]] and [[Glossary\|OSX]]. Examples are the [[Glossary\|Free Pascal]] compiler and [[Glossary\|Lazarus]], the [OpenOfficeOrg](http://www.openoffice.org) suite of office programs, the [Mozilla](http://www.mozilla.org) family of Web browsers and e-mail servers.
141	141
142	142		### CVS
143	143
144	144		[Concurrent Version System](http://www.cvshome.org/) (see also [[Glossary\|Subversion SVN]]). A system for producing orderly development of a software suite despite its use by multiple authors. A repository is set up, from which intending developers can check-out documents or files, and to which they can return edited material. Usually the posting of new or updated material is under the control of one or more moderators or administrators, and strict version control is maintained.
145	145
146	146		## D
147	147
148	148		### DataBase
149	149
150	150		A computer application designed for the structured storage of large amounts of data and for easy access to it. Many of the Web sites on the Internet make extensive use of databases: For example, a vendor may keep his catalogue of items for sale on a database, and may also keep his customer transactions on another related database; a software development team (like the Free Pascal team) might keep their library of programs and subprograms on a database; a medical research team might keep responses to their Case Report forms (CRFs) on a database.
151	151
152	152		Some typical examples are [MySQL](http://www.mysql.com), [PostgreSQL](http://www.postgresql.org/), [Oracle](http://www.oracle.com/index.html), [DB2](http://www-306.ibm.com/software/data/db2/). Many of these use a common standard [[Glossary\|Structured Query Language]] to place data in the database and retrieve it. Free Pascal/Lazarus has links to several of these databases.
153	153
154	154		A database system typically consists of the actual Data files, a Server which reads and writes to the files, and a Client which interprets the users instructions.
155	155
156	156		See also [[Databases]] entry in main Wiki
157	157
158	158		### [[Delphi]]
159	159
160	160		An excellent commercial [[Glossary\|Pascal-based]] [[Glossary\|RAD]] [[Glossary\|IDE]] for Windows made by [Borland](http://www.borland.com/).
161	161
162	162		[[Glossary\|Free Pascal]] sets out to be broadly compatible with Delphi, so that applications written by Delphi developers can be readily ported to Free Pascal/Lazarus, and the Free Pascal compiler has a Delphi compatability mode (using the compiler directive {\$MODE Delphi} or the command-line option -Sd).
163	163
164	164		However, slavish adherence to Delphi constructs and standards is no longer felt to be a requirement, and Free Pascal developers have improved on many of the Delphi constructs, in many cases producing a more flexible and more useful programming environment. All the procedures, functions, classes and other programming elements have been written from scratch by Free Pascal developers, quite independent of the Delphi code.
165	165
166	166		### Debugger
167	167
168	168		A computer program which can be used by developers to control the execution of a program in development, and show where a program is failing. Debuggers typically keep track of the location in the program (for example the line number in the source code), the contents of the variables in the program, and often produce a back-trace showing the instructions that were being executed immediately before the failure occurred in the program.
169	169
170	170		The Gnu Debugger [GDB](http://sourceware.org/gdb/) is used in Free Pascal/Lazarus systems; GDB must be present in the system. In Linux and other Unix-like systems the native Gnu/Linux version can easily be installed; in Windows systems a special Windows version of GDB has been included in the Lazarus release packages; alternatively GDB can be compiled from source for Windows and used in conjunction with the [CygWin](http://cygwin.com/) emulator.
171	171
172	172		At present the documentation on debugging for Free Pascal/Lazarus is not very complete, and users are advised to read the documentation on the GDB site carefully.
173	173
174	174		### [diff](http://www.gnu.org/software/diffutils/diffutils.html)
175	175
176	176		A GNU program used to show the differences between two files, or even two directories.
177	177
178	178		Used by software developers to check the changes in coding before committing an edited source file to a repository such as [[Glossary\|SVN]]. The output from diff can also be used to generate a Patch which can be applied to a source code file without having to re-write or re-import the whole file.
179	179
180	180		## E
181	181
182	182		## [[Editor]]
183	183
184	184		Text Editor — one of the essential tools of program development.
185	185
186	186		The source code of most computer programs consists of lines of text with the program instructions arranged in a logical sequence. Some form of text editor is necessary for inputting the source code and editing or correcting it.
187	187
188	188		All operating systems have available a number of text editors, some very primitive (such as ED or EDLIN in DOS/Windows or ED, vi in Unix/Linux) and some quite sophisticated (such as NotePad and WordPad in Windows, GEdit, KATE, KWrite and EMACS in Unix/Linux). It is even possible (though not recommended) to use Word Processor software for editing computer program source code.
189	189
190	190		Many text editors offer Syntax Highlighting (using different colours to show keywords, types of data or levels of nesting in statements) or have automatic indentation to make the structure of a program more apparent. Most have Search and/or Replace facilities, and can often recognise the beginning of Subprograms (Procedures and Functions) or open "include" files when required.
191	191
192	192		Both the [[Glossary\|Free Pascal]] and [[Glossary\|Lazarus]] [[Glossary\|IDEs]] have integral text editors which are the ones recommended for developing programs using the Free Pascal Compiler, but programs developed using any text editor can be passed to the compiler, provided they are syntactically and logically correct.
193	193
194	194		Each user will find his or her own favourite editor and come to recognise its advantages and limitations. And arguments between proponents of one or other editor are sometimes only slightly less heated than arguments about preferred Operating System!!
195	195
196	196		## F
197	197
198	198		### [[FCL]]
199	199
200	200		[[FCL\|Free Component Library]]
201	201
202	202		The main collection of components used by [[Glossary\|Free Pascal]]. See also [[Glossary\|RTL (Run Time Library)]] and [[Glossary\|LCL (Lazarus Component Library)]]
203	203
204	204		### Firebird
205	205
206	206		Free relational database system supported by FPC/Lazarus; see [[Firebird]]
207	207
208	208		### FORTRAN
209	209
210		-	~~Procedural language for <u>FOR</u>mula <u>TRAN</u>slation.~~
	210	+	Procedural language for FORmula TRANslation.
211	211
212	212		Once very popular for academic, scientific and engineering programs, its emphasis was on getting things done efficiently — very good for calculation-intense applications, but it made few concessions to ease of user interface.
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214	214		FORTRAN suffered from a rather rigid syntactic and formatting structure, though later versions have developed softer edges and make a few concessions to a windowed user environment with interactive input-output.
215	215
216	216		It is still one of the best languages for doing really hard sums, but is much less popular than languages with a friendlier user interface.
217	217
218	218		### FreeBSD
219	219
220	220		[[Portal:FreeBSD\|FreeBSD]] is an [[Glossary\|Operating System]] for a variety of platforms which focuses on features, speed, and stability. It is derived from BSD, the version of UNIX® developed at the University of California, Berkeley. It is developed and maintained by a large community.
221	221
222	222		### [Free Pascal](http://www.freepascal.org)
223	223
224	224		An [[Glossary\|OpenSource]] [[Glossary\|CrossPlatform]] [[Glossary\|Pascal]] [[Glossary\|Compiler]] which supports [[Glossary\|TurboPascal]]/BorlandPascal (TP/BP), [[Glossary\|Delphi]]/[[Glossary\|Kylix]] ([[Glossary\|OO]] or Object Pascal) and Apple syntax, also it has some extra addons like C-style macros and operators/symbols, Operator Overloading, auto function overloading and other nice features.
225	225
226	226		Free Pascal initially set out to reproduce the features of Delphi in an open-source environment, and offered the advantage of working on a number of operating system platforms, but it has acquired a character and ethos of its own, and slavish adherance to Delphi compatibility is no longer the fundamental driver. Free Pascal developers write code entirely independently from the Delphi sources.
227	227
228	228		Free Pascal consists of the [[Glossary\|compiler]] itself, a number of libraries including the Run-time library [[Glossary\|RTL]], the Free Pascal Component Library [[Glossary\|FCL]] and a number of optional packages that can be installed by the user. There is also an Integrated Development Environment ([[Glossary\|IDE]]) intended for use in a non-graphic text mode, and very similar to the TurboPascal IDE. Users who prefer to use a Graphical User Interface ([[Glossary\|GUI]]) can use one of a number of products, [[Glossary\|Lazarus]] being the best-known IDE which has been contributed to by over 120 programmers of whom some are closely involved with the Free Pascal project.
229	229
230	230		## G
231	231
232	232		### [GDB](http://www.gnu.org/software/gdb/gdb.html)
233	233
234	234		[[Glossary\|GNU]] [[Glossary\|Debugger]] used for debugging programs developed with the [[Glossary\|Free Pascal]] compiler, as well as programs in [[Glossary\|C]], [[Glossary\|C++]], [[Glossary\|FORTRAN]] and other languages.
235	235
236	236		### [GIMP](http://www.gimp.org/)
237	237
238	238		[[Glossary\|GNU]] Image Manipulation Program
239	239
240	240		One of the largest influences on Linux Graphics — it is a tool that some find hard to use at first, but it so infinitely configurable and intensively useful that most are eventually won over. The GIMP provides most of the [[Glossary\|Widgets]] (small graphic objects) used in the Gimp ToolKit (GTK) libraries that form one of the major sets of tools in Lazarus.
241	241
242	242		### [GNU](http://www.gnu.org/)
243	243
244	244		GNU is a wrapper around the [[Glossary\|Linux]] Kernel and Shell, providing a large number of user programs, user environments (both graphical and text-based), applications and development systems. It also contains a large number of libraries for use by various packages and systems. Its developers suggest that the [[Glossary\|Linux]] operating system should actually be described as the GNU/Linux OS, as the Linux kernel requires the functionality provided by GNU in order to work for the end-user.
245	245
246	246		From GNU's Website: GNU is a recursive acronym for “GNU's Not UNIX”; it is pronounced “guh-noo.” GNU is like [[Glossary\|UNIX]], but is not the same!
247	247
248	248		### [GTK](http://www.gtk.org/)
249	249
250	250		[[Glossary\|Gimp]] Tool Kit.
251	251
252	252		GTK+ is a multi-platform toolkit for creating graphical user interfaces, and [[Glossary\|Free Pascal]] and the [[Glossary\|Lazarus]] [[Glossary\|IDE]] make extensive use of GTK. It contains a set of [[Glossary\|Widgets]] or small graphical objects which can be incorporated into the forms or panels of applications.
253	253
254	254		### GUI
255	255
256	256		Graphical User Interface
257	257
258	258		A working environment in which a computer user is presented with a screen on which there are pictures or Icons representing programs, actions or files, and either uses a mouse cursor (or similar pointing device) to select the appropriate icon or uses a keyboard with directional buttons or keys to move around the screen and select the appropriate icon. There are often drop-down menus available when the mouse is placed over certain parts of the screen.
259	259
260	260		A GUI typically makes use of [[Glossary\|Object-Oriented]] or event-driven programming; instead of following a pre-determined sequence of actions, the application waits for an event such as a mouse-click over a particular icon, to determine what action is required and execute the appropriate piece of code; the application then goes back into the "wait" state until another event occurs, such as a mouse click over a different icon.
261	261
262	262		## H
263	263
264	264		## I
265	265
266	266		### IDE
267	267
268	268		Integrated Development Environment
269	269
270	270		It typically consists of a [[Glossary\|text editor]] for developing the program source, a [[Glossary\|Compiler]], perhaps an [[Glossary\|Assembler]] and a [[Glossary\|Linker]] to make construction and subsequent execution of the program quick and easy. It may also have access to a [[Glossary\|Debugger]] to help detect and correct logical or operational errors in the code.
271	271
272	272		### Interpreter
273	273
274	274		A software tool that examines an input stream of computer-language instructions (from the console or from a text-file) and converts them into machine-code instructions which are then immediately executed. This differs from a [[Glossary\|compiler]] (which converts a whole file into machine instructions and then stores the code for subsequent execution) in that instructions are interpreted line-by-line, and the conversion process has to happen every time the program is run.
275	275
276	276		The [[Glossary\|Command-Line interpreters]] in [[Glossary\|Linux]], [[Glossary\|Windows]], IBM systems and DEC PDP and VAX systems are good examples. Several popular programming languages are interpretive rather than compiled. The best examples are [[Glossary\|BASIC]] (in all its variants including Visual BASIC), PERL, Python and [[Glossary\|Java]]. Interpreted-language programs are generally several orders of magnitude slower than compiled-language programs because of the need to re-interpret the commands before execution every time, but they have the great advantage that changes are easily made, new code can be tested quickly, and often speed is not all that important compared with ease of development. Some languages (including various dialects of BASIC) offer the programmer an opportunity to try out a program first in interpreted mode, then when the program works correctly and no more changes are necessary, the whole program can be compiled to produce a much faster product.
277	277
278	278		Some variants of Pascal, including [[UCSD Pascal]] from the University of California at San Diego (UCSD), offered a peculiar combination of compiled and interpreted operation: The textual Pascal source code was first converted into an intermediate P-code, which was then passed on to a P-code interpreter that translated and executed it.
279	279
280	280		## J
281	281
282	282		### Java
283	283
284	284		Computer language developed by Sun Microsystems for writing Web-based applications. It is an [[Glossary\|interpreted language]] (which tends to produce rather slowly-running programs), but applications can be written rapidly and ported to a large number of different processors and machines. It has facilities for [[Glossary\|Object-Oriented Programming]].
285	285
286	286		See also: [[Pascal for Java users]]
287	287
288	288		## K
289	289
290	290		### Kylix
291	291
292	292		Delphi-like Rad Tool for Linux made by Borland. It is based on Delphi, and uses the [[Glossary\|QT]] / CLX [[Glossary\|widget]] set. It attempts to port Delphi's IDE to Linux by using [WINE](http://www.winehq.org/), a Windows Emulator program, rather than translating the code for the IDE into proper Linux-specific code, and hence operates rather slowly and patchily. Borland seem to have lost interest in developing or supporting Kylix further, and many former users of Kylix have migrated to Free Pascal/Lazarus as the only viable alternative for Pascal development in Linux.
293	293
294	294		## L
295	295
296	296		### [Lazarus](http://lazarus.freepascal.org)
297	297
298	298		A [[Glossary\|CrossPlatform]] [[Glossary\|RAD]] [[Glossary\|IDE]] made with [[Glossary\|Free Pascal]] and designed to use Free Pascal as its programming language and compilation tool. It has many of the features of the IDE found in Borland's [[Glossary\|Delphi]] and [[Glossary\|Kylix]] (although all the code has been written independently), and has some features which are missing from Delphi/Kylix, while lacking a few of the features found in the Borland products.
299	299
300	300		Its main user interface includes a Source Code [[Glossary\|Editor]], a Main Menu bar containing the Component Palette, a Form Design Window and an Object Inspector. Other features include a Documentation editor, considerable Code Help, and access to extensive libraries of components and packages.
301	301
302	302		Developers typically use the IDE's Form Designer to sketch out the physical structure of their applications, use the Source Code Editor to add programming instructions to respond to events occurring during program execution, and then use the built-in Free Pascal compiler and linker to produce executable code. During execution of the code, the [[Glossary\|debugger]] is used to trap errors and find logical problems in the program.
303	303
304	304		The IDE can even be used to rebuild Lazarus itself, when corrections or updates are received, for example, from the [[Glossary\|SVN]] repositories.
305	305
306	306		### LCL
307	307
308	308		[[LCL\|Lazarus Component Library]], contains a large number of units defining classes, components and methods for creating applications using [[Glossary\|Free Pascal]]. The LCL consists mainly of visual components and objects, often called [[Glossary\|Widgets]]: some examples are Buttons, Labels, Edit Boxes, Drop-down Lists, Popup Menus, Images and Grids. The non-visual elements such as file handling and database management are found in the [[Glossary\|Free Pascal Component Library]] and [[Glossary\|Run Time Library]]. Many of the components defined in the LCL and other libraries are used to build the Lazarus [[Glossary\|IDE]].
309	309
310	310		See [[Lazarus Components]] for a list of components available, and their equivalent in TurboPascal and Delphi.
311	311
312	312		### Linker
313	313
314	314		A computer program that takes the output from a [[Glossary\|Compiler]] and finds any pre-compiled library routines that are needed, and joins them all together to produce an executable program.
315	315
316	316		### [Linux](http://www.linux.org/)
317	317
318	318		[[Linux]] is an [[Glossary\|Open Source]] [[Glossary\|Operating System]] derived originally from [[Glossary\|Unix]], but totally re-built using Open Source code, and receiving contributions from literally thousands of developers. Today it is one of the most popular Operating Systems. It is one of the platforms for which [[Glossary\|Free Pascal]] and [[Glossary\|Lazarus]] are built, and one of the platforms extensively used for their development.
319	319
320	320		## M
321	321
322	322		### MAC
323	323
324	324		- In computer hardware, Mac refers to Apple Macintosh computers.
325	325
326	326		- In networking, MAC means Media Access Control or Medium Access Control, a low level unique identifier for a network interface card (NIC) which it is possible to easily change via software.
327	327
328	328		### macOS
329	329
330	330		- Refers to the Macintosh computer [[Glossary\|Operating System]] from Apple, it is famous for its high quality graphics and stability. Since 2001 macOS has been based on [[Glossary\|UNIX®]] and shares many commonalities with [[Glossary\|FreeBSD]] and some commonalities with [[Glossary\|Linux]]. It is capable of running the [[Glossary\|X Window System (X11)]] windowing system for bitmap displays, common on Unix-like operating systems. macOS was previously marketed as [[Glossary\|Mac OS X]] until 2012 and [[Glossary\|OS X]] until 2016. After Windows, it is the most popular desktop Operating System.
331	331
332	332		### Mac OS
333	333
334	334		In 1984, Apple debuted the [[Glossary\|Operating System]] that is now known as the "Classic" Mac OS with its release of the original Macintosh System Software. The system, rebranded "Mac OS" in 1996, was preinstalled on every Apple Macintosh computer until 2002 and offered on Macintosh clones for a short time in the 1990s. Noted for its ease of use, it was also criticized for its lack of modern technologies compared to its competitors.
335	335
336	336		### Mac OS X
337	337
338	338		The first desktop version (version 10.0) of the Apple Macintosh [[Glossary\|Operating System]] known as Mac OS X was released in March 2001. With the release of Mountain Lion (version 10.8) in 2012 Apple shortened the name to [[Glossary\|OS X]] and then changed it to [[Glossary\|macOS]] in 2016.
339	339
340	340		### MariaDB
341	341
342	342		Fork of MySQL; aims to be compatible but more generously licensed for commercial use.
343	343
344	344		### Mormot
345	345
346	346		mORMot : Synopse [[mORMot]] is an Open Source Client-Server ORM SOA MVC framework for FPC, targeting Win/Linux for the server, and any platform for clients (including mobile or AJAX). In other words, nobody knows what it is supposed to be but a heap of gibberish.
347	347
348	348		### MySQL
349	349
350	350		Relational database system; see [[MySQL]].
351	351
352	352		## N
353	353
354	354		## O
355	355
356	356		### Object
357	357
358	358		A special type of [[Glossary\|Record]] used in [[Glossary\|Free Pascal]] and other high-level [[Glossary\|Object Oriented]] languages. As well as containing a group of data Fields (as in a conventional Record), an Object can define Methods (Procedures and Functions, either static, virtual or non-virtual) for processing the data in the fields. For example, an object could contain an array of real values, together with a Method for calculating the average.
359	359
360	360		``` pascal
361	361		Type
362	362		Average = Object
363	363		NumVal: Integer;
364	364		Values: Array [1..200] of Real;
365	365		Function Mean : Real; { calculates the average value of the array }
366	366		End;
367	367		```
368	368
369	369		Or a Button placed on a Form in a graphical environment might have the following structure (highly simplified):
370	370
371	371		``` pascal
372	372		Type
373	373		Button = Object
374	374		Top, Left: Integer; { screen coordinates to define button's position }
375	375		Height, width: Integer;
376	376		Color: TColor;
377	377		Caption : String;
378	378		Procedure OnClick; { method invoked when the mouse is clicked on the Button's image}
379	379		End;
380	380		```
381	381
382	382		The Procedure or Function in the above definition must, of course, be declared elsewhere in the program, typically in an Implementation section.
383	383
384	384		See also [[Glossary\|Classes]]
385	385
386	386		### OO
387	387
388	388		Object Oriented
389	389
390	390		Extension to a procedural language which enables the creation and manipulation of complicated [[Glossary\|Objects]].
391	391
392	392		While Standard [[Glossary\|Pascal]] maintains a [[Glossary\|Record]] structure, in which various different data types such as [[Integer\|integers]], reals, arrays, [[String\|strings]] and [[Pointer\|pointers]] can co-exist in a predefined way, an object-oriented language like [[Glossary\|Free Pascal]] allows the structure also to contain Methods (procedures and functions) for the manipulation of the data elements within the structure.
393	393
394	394		See also [[Object Oriented Programming with Free Pascal and Lazarus]]
395	395
396	396		### Open Source
397	397
398	398		A system of software development based on publishing all your source code where it is freely available for others to view, copy, compile and use, and also to correct, modify and improve. Users, developers or modifiers are simply required or expected to acknowledge where the source came from, how they have changed it, and make the source available to anyone to whom they give or sell their program. It exists in contrast to the usual commercial model of software development, where programs are shrouded in secrecy and patent/copyright legality, only a few members of the team have access to the code, and the end user has no idea of how the program works or how to fix it if it breaks.
399	399
400	400		From the outset, [[Glossary\|Free Pascal]] and [[Glossary\|Lazarus]] have been developed as open source programs, with all the source code freely available to anybody who wants to use it, and with encouragement to all to try it out, suggest bug-fixes, attempt to improve it or complete the parts that have not been implemented, and generally contribute to its development. This approach has led to an excellent cooperative effort, rapid development of the system and a development environment that is completely transparent for all its users.
401	401
402	402		### OS
403	403
404	404		The Operating System is a program that controls the basic performance of a computer. It deals with the input-output functions of the various parts (such as keyboard, mouse, video display, disk storage, memory and peripherals such as serial, parallel and USB interfaces); it controls scheduling of tasks and allocation of processing time between processes and users; it traps system errors and performs a host of other functions. Most of these activities proceed without the user being aware of them.
405	405
406	406		An operating system usually has a part called the kernel (i.e., the most deeply embedded part of the program) which is started by the BIOS (Basic Input-Output System of the computer) and it has various libraries which provide an interface with the computer hardware. The Kernel can also be considered an abstraction layer between the applications and the electronics part.
407	407
408	408		There is often another "layer", called the shell, which represents an interface between the Kernel and the user who types commands on a keyboard or moves a mouse around the table to select commands displayed on the screen.
409	409
410	410		An Operating Systems can operate in Console (Text) or Graphical Mode. Most modern Operating Systems support threading and are multitasking, allowing multiple programs to run at the same time.
411	411
412	412		### OS X
413	413
414	414		The first desktop version (version 10.0) of the Apple Macintosh [[Glossary\|Operating System]] known as [[Glossary\|Mac OS X]] was released in March 2001. With the release of Mountain Lion (version 10.8) in 2012 Apple shortened the name to OS X and then changed it to [[Glossary\|macOS]] in 2016.
415	415
416	416		## P
417	417
418	418		### [Pascal](http://en.wikipedia.org/wiki/Pascal_programming_language)
419	419
420	420		Pascal is a procedural programming language, designed in 1968–1969 and published in 1970 by Niklaus Wirth (see [[Basic Pascal Tutorial/History\|Pascal History]], [[Why use Pascal]]).
421	421
422	422		There is an international standard definition of the language (ISO 7185, equivalent to ANSI/IEEE770X3.97), but apart from [Gnu Pascal](http://www.gnu-pascal.de/gpc/h-index.html) ([[Glossary\|Open Source]]) and Prospero Pascal (a commercial product available only for [[Glossary\|Windows]] systems), not many of the modern implementations conform exactly to the Standard. However, they are all essentially similar in syntax and structure, and programs written for one variant are fairly interchangeable with others.
423	423
424	424		[[Glossary\|Free Pascal]], [[Glossary\|Delphi]] and other variants of Pascal have Object Oriented extensions.
425	425
426	426		### PDA
427	427
428	428		Personal Digital Assistant — a pocket-sized (or Palm-sized) device on which information such as address-books, calendars and other useful information can be stored. These devices (such as the Palm-Pilot and the Compaq Pocket-PC) are becoming increasing sophisticated, and the Sharp [[Glossary\|Zaurus]] which has a [[Glossary\|Linux]] operating system is a popular vehicle for experimenters and developers.
429	429
430	430		There is a [[Glossary\|Free Pascal]] [[Glossary\|cross-compiler]] available, which allows Pascal programs compiled on a PC to be run on the Zaurus, and there is also a WinCE [[Glossary\|cross-compiler]] branch of FPC that allows applications to be developed in Windows for operation on the Pocket-PC.
431	431
432	432		The PDA functions are now largely incorporated into SmartPhones and portable Tablet computers, most of which run the Android operating system, a Pascal-derived OS developed by Google. Some Lazarus developers are producing applications for the Android platform.
433	433
434	434		### PostgreSQL
435	435
436	436		Free relational database system supported by FPC/Lazarus; see [[postgresql\|PostgreSQL]]
437	437
438	438		## Q
439	439
440	440		### [Qt interface](http://wiki.lazarus.freepascal.org/index.php/Qt_Interface)
441	441
442	442		Qt is one of the major [[Glossary\|widget]] sets used in Linux, and forms the basis for the KDE (K-desktop environment). It is one of the libraries of widgets actively supported by Lazarus-FPC, though it is not as well-established as the GTK libraries.
443	443
444	444		## R
445	445
446	446		### RAD
447	447
448	448		Rapid Application Development (Examples: [[Glossary\|Delphi]], [[Glossary\|Lazarus]], Visual Basic)
449	449
450	450		A software package for the fast and easy creation of Applications (Programs). Typically includes a [[Glossary\|text editor]], a [[Glossary\|graphic user interface]], and easy links to various tools such as [[Glossary\|compilers]], [[Glossary\|linkers]] and [[Glossary\|debuggers]]. Frequently offers an Integrated Development Environment ([[Glossary\|IDE]]).
451	451
452	452		### [[Record]]
453	453
454	454		A highly structured data type in [[Glossary\|Pascal]] and other high-level languages.
455	455
456	456		While simple data structures such as arrays or sets consist of elements all of the same type, a record can consist of a number of elements of different types, and can take on a huge complexity.
457	457
458	458		Records are widely used in Pascal, to group data items together logically. They also form the basis for even more complicated structured types such as [[Glossary\|Objects]] and [[Glossary\|Classes]], used in [[Glossary\|Object Oriented]] programming. See also: [[Record]]
459	459
460	460		### [[RTL]]
461	461
462	462		[[RTL\|Runtime Library]]
463	463
464	464		The library of components in [[Glossary\|Free Pascal]] which are used at run-time to translate instructions from programs according to the operating system and computer architecture of the current platform. See also [[Glossary\|Free Pascal Component Library FCL]]
465	465
466	466		### [[RTTI]]
467	467
468	468		Runtime Type Information
469	469
470	470		Keeping the data-types of objects available at runtime. Can be useful for streaming and typecasting objects.
471	471
472	472		## S
473	473
474	474		### Startup
475	475
476	476		[[Startup]]
477	477
478	478		### SQL
479	479
480	480		Structured Query Language.
481	481
482	482		An universal script language used in various types of [[Glossary\|DataBases]] with a defined syntax to be used for execution of queries.
483	483
484	484		### SVN
485	485
486	486		[Subversion](http://subversion.tigris.org/)
487	487
488	488		A document version control system designed to improve upon and ultimately to replace [[Glossary\|CVS]].
489	489
490	490		SVN is the document management system currently used by both the [[Glossary\|Free Pascal]] and the [[Glossary\|Lazarus]] projects.
491	491
492	492		## T
493	493
494	494		### [[Turbo Pascal]]
495	495
496	496		A Pascal compiler produced by Borland which revolutionised Pascal development on PCs and microcomputers.
497	497
498	498		Previous Pascal compilers were huge and cumbersome, or slow, or expensive, or all three.
499	499
500	500		Borland's TurboPascal was very fast, very economic in resources, and very cheap.
501	501
502	502		Unfortunately it did not comply in all respects with the ISO standard, notably in its handling of the get() and put() functions with text files.
503	503
504	504		However it has been very popular, and with object oriented extensions it formed the basis of Delphi (which, though it has a stripped-down free no-cost version, is rather expensive if you want to do serious computing) and Kylix, the Linux version of Delphi.
505	505
506	506		It also forms the foundation for Free Pascal and Lazarus, but the main difference between Borland's compilers and Free Pascal is that the source is not available for Borland, whereas all the sources for Free Pascal are readily available. Borland compilers are commercial (even if offered at no-cost) but Free Pascal and Lazarus are free ([[Glossary\|open-source]]).
507	507
508	508		## U
509	509
510	510		### Unix
511	511
512	512		One of the first [[Glossary\|Operating Systems]]. It was written in [[Glossary\|C]] and had threading and multi-process capabilities; later Linus Torvalds and other programmers made an Open Source system resembling Unix called [[Glossary\|Linux]] which is one of the most popular Operating Systems today. Others followed the example and other Operating Systems were born: FreeBSD, OpenBSD, NetBSD and many others; also Apple introduced Open Source parts of various Unix clones and made MAC OS X which is famous for its graphical features and stability.
513	513
514	514		### [[Unit]]
515	515
516	516		A Pascal source file is also called a unit and usually has .pas, .pp or .p extension.
517	517
518	518		The Pascal unit has an internal name which is usually the first line of the unit "unit MyUnit;", where MyUnit is the internal name.
519	519
520	520		The unit also has two main sections interface and implementation which are similar in C/C++ terminology to the header (.h, .hpp, .hh) file and the body file (.c, .cpp, .cc).
521	521
522	522		All the code in the interface section can be accessed by other units or program files that "use" this unit: this is done by the uses clause. The [[Glossary\|uses]] clause can appear either in the interface or implementation section: the code in the implementation section is "private" and can only be accessed by the same unit unless it is redefined in the interface section which is the case for "global" procedures and functions.\
523	523		The Pascal unit can also contain two more sections, initialization and finalization: these are executed automatically when the main program starts and stops using this unit, as their names suggest.
524	524
525	525		### [[Uses]]
526	526
527	527		Clause in an Object Pascal program: a line near the top of the file or [[Glossary\|Unit]] (in either the interface or the implementation) which lists other units that need to be accessed to find [[Glossary\|components]] used in the program.
528	528
529	529		For Example:
530	530
531	531		``` pascal
532	532		uses
533	533		Classes, SysUtils, MySpecialUnit;
534	534		```
535	535
536	536		## V
537	537
538	538		### VCL
539	539
540	540		Visual Component Library — Base of Delphi Components Classes.
541	541
542	542		### V4L
543	543
544	544		Video For Linux
545	545
546	546		### VFW
547	547
548	548		Video For Windows
549	549
550	550		## W
551	551
552	552		### Widget
553	553
554	554		A small (or even large!) graphical object or image, often part of a larger image, form, screen or picture. [[Glossary\|Object Oriented]] programs often depend heavily on the use of Forms, which comprise a large number of widgets such as buttons, captions, edit boxes, scroll bars, titles, menu bars, panels, grids and pictorial images like photos or drawings.
555	555
556	556		[[Glossary\|Lazarus]] has separate [[Widgetset\|widget sets]] for each Window Manager system, such as Microsoft Windows (widget sets [[Win32/64 Interface\|Win32/64]], or [[Windows CE Interface\|WinCE]] for hand-held devices), Linux ([GTK widgetsets](/wiki-category/GTK%20Widgetsets) for Gnome-based systems, [[Qt Interface\|Qt]] for KDE systems), Apple (widget sets [[Carbon Interface\|Carbon]] and [[Cocoa Interface\|Cocoa]]) as well as some non-specific sets such as [[Custom Drawn Interface\|CustomDrawn]], [[fpGUI]] or [[nvidia-widgets\|nvidia widgets]].
557	557
558	558		Lazarus developers have had to design custom-built interfaces to each widget set: the aim is to provide an interface of which the user is unaware; he or she simply writes the code or designs the form, and the widgets of the relevant set for his operating system fit into place and work seamlessly.
559	559
560	560		### Wiki
561	561
562	562		A type of Web site that provides documentation for a software package or similar information, and that welcomes editorial activity, additions and comments from the community. Most Wiki sites require potential users to register, and then login in order to edit the site. Documentation can be developed very quickly and flexibly.
563	563
564	564		The [[Main Page\|Lazarus and Free Pascal Wiki]] site that you are currently browsing contains extensive documentation about the [[Glossary\|Free Pascal]] and [[Glossary\|Lazarus]] projects. Users and developers are actively encouraged to [register](http://wiki.lazarus.freepascal.org/index.php?title=Special:Userlogin&returnto=Special:Userlogout) and submit their contributions.
565	565
566	566		### WinCE
567	567
568	568		A Windows-like environment for portable hand-held devices, mobile phones, PDAs, etc. Produced by Microsoft, it has many features that resemble [[Glossary\|Windows]] for desktops, but represents a "cut-down" version.
569	569
570	570		Most hand-helds use the ARM processor, and a [[WinCE port]] of [[Glossary\|Free Pascal]] and [[Glossary\|Lazarus]] has been constructed to allow applications for the ARM and WinCE to be [[Glossary\|cross-compiled]] and loaded for running on the hand-held device.
571	571
572	572		For more details see [[Windows CE Development Notes]] and [[Windows CE Interface]]
573	573
574	574		### Windows
575	575
576	576		An [[Glossary\|Operating System]] from Microsoft, probably the most widely used Operating System today, famous for its user friendly interface but infamous for its vulnerability to malicious attackers.
577	577
578	578		"Windows" also refers to rectangular areas on a computer screen which contain the textual and graphical material associated with a particular process or application. A window may form part of a program or system other than Microsoft's offering, for example there can be X-windows (see [[Glossary\|X11]]) or simple text-windows used by inherently text-based systems.
579	579
580	580		## X
581	581
582	582		### [X11](http://www.x.org/wiki/)
583	583
584	584		Also called XFree, Xorg or simply X is a graphical interface originally designed for [[Glossary Unix\|Unix]] and also widely used in [[Glossary\|Linux]].
585	585
586	586		The X11 concept is quite different from the Windows GDI mainly because XFree is a program, not just a set of libraries. Because X11 is more hardware oriented and doesn't have a full set of [[Glossary\|widgets]] yet, some programmers developed more advanced widgets like [[Glossary\|GTK]] and [[Glossary\|QT]] and various Window Managers and Desktop Environments like GNOME, KDE, XPde, XFCE, IceWM, WindowMaker and many others.
587	587
588	588		For more information about X11 please visit the [XFree Web site](http://www.x.org).
589	589
590	590		## Y
591	591
592	592		## Z
593	593
594	594		### Zaurus
595	595
596	596		[[Glossary\|PDA]] made by Sharp that uses Linux as its operating system. Its processor is the ARM for which a port of the Free Pascal compiler has been made, and it is possible to cross-compile applications in Free Pascal that will run on the Zaurus
597	597
598	598		---
599	599		From the Free Pascal wiki, page "Glossary", as it stood on 2022-09-05 after a change by Kai Burghardt, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).
600	600		Category: Glossary
601	601		Category: Main

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