STEP 2: What is LaTeX
To use LaTeX, a TeX program is required which is a computer program for typesetting documents. It is not a word processor, i.e. you have to type a source file containing special typesetting commands using a text editor and then process the file by means of TeX or LaTeX. Simple documents that do not contain mathematical formulae or tables may be produced very easily. Typesetting mathematics is somewhat more involved, but even here TeX is comparatively straightforward to use, considering the complexity of the formulae that it is required to typeset. The software also has facilities for the development of equations.
LaTeX is a TeX macro package which enables authors to typeset and print their work at the highest typographical quality, using a predefined, professional layout. It is particularly suited to the production of long articles and books, since it has the capability for the automatic numbering of chapters, sections, theorems, equations, etc., and can automate cross-referencing. LaTeX2e is probably one of the most suitable versions of LaTeX for beginners to use.
LaTeX program reads in text from an input file, which is a text file with .tex extension, and creates a `DVI file' which encodes information on the fonts to be used and the positioning of the characters on the printed page. The text file can be developed using text editors like MS Notepad or iv, word processors such as MS Word or WordPerfect or text editors especially created for editing TeX and LaTeX files like WinEdt. Many programs are available to translate the `DVI file' into page description languages such as `PostScript', convert it into the format appropriate for previewing the document on a computer screen, e.g. PDF, or for printing it.