# LaTeX

LaTeX
File:LaTeX logo.svg
Original author(s) Leslie Lamport
Platform Cross-platform
Type Typesetting
Website latex-project.org

LaTeX (pronounced /ˈleɪtɛk/, /ˈleɪtɛx/, or /ˈlɑːtɛk/) is a document markup language and document preparation system for the TeX typesetting program. Within the typesetting system, its name is styled as File:LaTeX logo.svg.

LaTeX is most widely used by mathematicians, scientists, engineers, philosophers, economists and other scholars in academia and the commercial world, and other professionals. [1][2] As a primary or intermediate format (e.g. translating DocBook and other XML-based formats to PDF), LaTeX is used because of the high quality of typesetting achievable by TeX. The typesetting system offers programmable desktop publishing features and extensive facilities for automating most aspects of typesetting and desktop publishing, including numbering and cross-referencing, tables and figures, page layout and bibliographies. LaTeX is intended to provide a high-level language that accesses the power of TeX. LaTeX essentially comprises a collection of TeX macros and a program to process LaTeX documents. Because the TeX formatting commands are very low-level, it is usually much simpler for end-users to use LaTeX.

LaTeX was originally written in the early 1980s by Leslie Lamport at SRI International.[3] It has become the dominant method for using TeX—relatively few people write in plain TeX anymore. The current version is LaTeX2e (styled File:LaTeX2e logo.svg).

The term LaTeX refers only to the language in which documents are written, not to the editor used to write those documents. In order to create a document in LaTeX, a .tex file must be created using some form of text editor. While most text editors can be used to create a LaTeX document, a number of editors have been created specifically for working with LaTeX.

## Typesetting system

LaTeX is based on the idea that authors should be able to focus on the content of what they are writing without being distracted by its visual presentation. In preparing a LaTeX document, the author specifies the logical structure using familiar concepts such as chapter, section, table, figure, etc., and lets the LaTeX system worry about the presentation of these structures. It therefore encourages the separation of layout from content while still allowing manual typesetting adjustments where needed. This is similar to the mechanism by which many word processors allow styles to be defined globally for an entire document or the use of Cascading Style Sheets to style HTML.

LaTeX can be arbitrarily extended by using the underlying macro language to develop custom formats. Such macros are often collected into packages, which are available to address special formatting issues such as complicated mathematical content or graphics. Indeed, in the example below, the align environment is provided by the amsmath package.

## Example

The example below shows the LaTeX input and corresponding output:

 \documentclass[12pt]{article} \usepackage{amsmath} \title{\LaTeX} \date{} \begin{document} \maketitle \LaTeX{} is a document preparation system for the \TeX{} typesetting program. It offers programmable desktop publishing features and extensive facilities for automating most aspects of typesetting and desktop publishing, including numbering and cross-referencing, tables and figures, page layout, bibliographies, and much more. \LaTeX{} was originally written in 1984 by Leslie Lamport and has become the dominant method for using \TeX; few people write in plain \TeX{} anymore. The current version is \LaTeXe.   % This is a comment; it is not shown in the final output. % The following shows a little of the typesetting power of LaTeX \begin{align} E &= mc^2 \\ m &= \frac{m_0}{\sqrt{1-\frac{v^2}{c^2}}} \end{align} \end{document} File:LaTeX Output.svg

## Pronouncing and writing "LaTeX"

File:Latexgraphic.svg
LaTeX can also be used to produce vector graphics.

LaTeX is usually pronounced /ˈleɪtɛk/ or /ˈlɑːtɛk/ in English (that is, not with the /ks/ pronunciation English speakers normally associate with X, but with a /k/). The characters T, E, X in the name come from capital Greek letters tau, epsilon, and chi, as the name of TeX derives from the Template:Lang-el (skill, art, technique); for this reason, TeX's creator Donald Knuth promotes a /tɛx/ pronunciation[4] (that is, with a voiceless velar fricative as in Modern Greek, or the last sound of the German word "Bach", similar to the Spanish "j" sound, or as ch in loch). Lamport, on the other hand, has said he does not favor or discourage any pronunciation for LaTeX.

The name is traditionally printed with the special typographical logo shown at the top of this page. In media where the logo cannot be precisely reproduced in running text, the word is typically given the unique capitalization LaTeX to avoid confusion with the word "latex". The TeX, LaTeX [5] and XeTeX [6] logos can be rendered via pure CSS and XHTML for use in graphical web browsers following the specifications of the internal \LaTeX macro.[7]

## Licensing

LaTeX is typically distributed along with plain TeX. It is distributed under a free software license, the LaTeX Project Public License (LPPL). The LPPL is not compatible with the GNU General Public License, as it requires that modified files must be clearly differentiable from their originals (usually by changing the filename); this was done to ensure that files that depend on other files will produce the expected behavior and avoid dependency hell. The LPPL is DFSG compliant as of version 1.3. As free/open source software, LaTeX is available on most operating systems including Unix (including Linux and the BSDs), Windows, Mac OS X, RISC OS and AmigaOS.

## Related software

As a macro package, LaTeX provides a set of macros for TeX to interpret. There are many other macro packages for TeX, including Plain TeX, GNU Texinfo, AMSTeX, and ConTeXt.

When TeX "compiles" a document, the processing sequence (from the user's point of view) goes like this: Macros > TeX > Driver > Output. Different implementations of each of these steps are typically available in TeX distributions. Traditional TeX will output a DVI file, which is usually converted to a PostScript file. More recently, Hàn Thế Thành and others have written a new implementation of TeX called pdfTeX, which also outputs to PDF and takes advantages of features available in that format. The XeTeX engine developed by Jonathan Kew merges modern font technologies and Unicode with TeX.

The default font for LaTeX is Knuth's Computer Modern, which gives default documents created with LaTeX the same distinctive look as those created with plain TeX. XeTeX allows to use OpenType and TrueType (that is, outlined) fonts for output files.

There are also many editors for LaTeX, listed in section See also.

## Versions

LaTeX2e is the current version of LaTeX. As of 2010, a future version called LaTeX3, started in the early 1990s, is still in development.[8] Planned features include improved syntax, hyperlink support, a new user interface, access to arbitrary fonts, and new documentation.[9]

There are numerous commercial implementations of the entire TeX system. System vendors may add extra features like additional typefaces and telephone support. LyX is a free, WYSIWYM visual document processor that uses LaTeX for a back-end. TeXmacs is a free, WYSIWYG editor with similar functionalities as LaTeX but a different typesetting engine. Other WYSIWYG editors that produce LaTeX include Scientific Word on MS Windows.

A number of TeX distributions are available, including TeX Live (multiplatform), teTeX (deprecated in favour of TeX Live, Unix), fpTeX (deprecated), MiKTeX (Windows; for Linux in the upcoming version 2.8), MacTeX, gwTeX (Mac OS X), OzTeX (Mac OS Classic), AmigaTeX (no longer available) and PasTeX (AmigaOS, available on the Aminet repository).

• Comparison of TeX editors
• AMS-LaTeX - American Mathematical Society extension for LaTeX
• ConTeXt - macro package for TeX, distinct from LaTeX
• DocBook
• BibTeX reference management software typically used with LaTeX
• Gummi free open source LaTeX editor (Linux, Gnome)
• Kile free open source LaTeX editor (Linux, KDE)
• LyX free open source GUI-based editor that uses LaTeX for typesetting
• MathMagic WYSIWYG LaTeX equation editor and Math symbol fonts
• New Typesetting System NTS - a TeX reimplementation (discontinued)
• TeXmacs A WYSIWYG TeX-based editor
• Texmaker free open source cross-platform LaTeX editor
• TexMakerX TexMakerX is a fork of the LaTeX IDE TexMaker (free)
• TeXShop free open source LaTeX editor (Mac OS X)
• TeXworks free open source LaTeX editor (Windows, GNU/Linux, Mac OS X) [10]
• Verbosus browser based, platform independent LaTeX editor
• TeXnicCenter free open source LaTeX editor (Windows)
• VIM-LaTeX or LaTeX-Suite (project's site) a comprehensive set of tools to view, edit and compile LaTeX documents inside the Vim text editor
• WinShell A free multilingual integrated development environment (IDE) for LaTeX and TeX
• XyMTeX A macro package for rendering high-quality chemical structures
• LaTeXPiX, a freeware graphical editor generating drawings in many formats (EEPICS, PGF, PSTRICKS), written for Windows OS.

## References

1.
2. Alexia Gaudeul (March 27, 2006). "Do Open Source Developers Respond to Competition?: The (La)TeX Case Study".
3. Leslie Lamport (April 23, 2007). "The Writings of Leslie Lamport: LaTeX: A Document Preparation System". Leslie Lamport's Home Page. Retrieved 2007-04-27.
4. Donald E. Knuth, The TeXbook, Addison–Wesley, Boston, 1986, p. 1.
5. O'Connor, Edward. "TeX and LaTeX logo POSHlets". Retrieved 2008-04-21.
6. Taraborelli, Dario. "CSS-driven TeX logos". Retrieved 2008-04-21.
7. Walden, David (2005-07-15). "Travels in TeX Land: A Macro, Three Software Packages, and the Trouble with TeX". The PracTeX journal (3). Retrieved 2008-04-21.
8. See e.g. [1]. Furthermore, all LaTeX3 components actually carry the copyright notice "(C) 1990-2006 LaTeX3 project", e.g. [2].
9. Frank Mittelbach, Chris Rowley (January 12, 1999). "The LaTeX3 Project" (PDF). Retrieved 2007-07-30.
10. Jonathan Kew (April 12, 2009). "TeXworks - lowering the entry barrier to the TeX world".

• Griffiths, David F.; Highman, David S. (1997). Learning LaTeX. Philadelphia: Society for Industrial and Applied Mathematics. ISBN 0-898-71383-8.
• Kopka, Helmut; Daly, Patrick W. (2003). Guide to LaTeX (4th ed.). Addison-Wesley Professional. ISBN 0-321-17385-6.
• Lamport, Leslie (1994). LaTeX: A document preparation system: User's guide and reference. illustrations by Duane Bibby (2nd ed.). Reading, Mass: Addison-Wesley Professional. ISBN 0-201-52983-1.
• Mittelbach, Frank; Goosens, Michel (2004). The LaTeX Companion (2nd ed.). Addison-Wesley. ISBN 0-201-36299-6.