What is TeX and LaTeX?

TeX

TeX is a program for quality typesetting. It was developed by Donald Knuth in the years 1978-88, and it has the following properties:

• TeX is not a WYSIWYG (`what you see is what you get') system. The text is interspersed with commands that control the typesetting process. The command langauge is extensible, so the user can define his or her own commands.
• TeX produces typeset documents of the highest quality. It is particularly strong on complicated mathematics.
• The TeX program runs on just about every kind of computer in existence today, from 286 PCs and upward.
• There are free implementations available on all these computers, see CTAN (Comprehensive TeX Archive Network).
• There is a large user base, so there is no shortage of helpful experts; some are organized in user groups like NTUG

The TeX program is fully described in

Donald E. Knuth: The TeXbook
Addison-Wesley 1991, ISBN 0-201-13447-0.

LaTeX

LaTeX is the most widely used extension of TeX; it was developed by Lesley Lamport in 1985 and has the following properties:

• LaTeX is a structure oriented system in which the user combines text and structure commands; the same idea is used in SGML and HTML.
• The actual typesetting is done according to a style sheet (called a `document class' in LaTeX) defining the layout. Many document classes exist, and the user can easily make his or her own.
• LaTeX is free, and it is very easy to install on top of a running TeX system.

A good book for LaTeX beginners is the originator's own introduction

Leslie Lamport: LaTeX -- a document preparation system -- user's guide (2nd edition)
Addison-Wesley 1994, ISBN 0-201-52983-1.

More advanced users will benefit from

Michel Goossens, Frank Mittelbach: The LaTeX companion – 2nd edition
Pearson 2004, ISBN 0-201-36299-6.