This page is for the benefit of new TeX system users. As such, it tries to be short and simple. An even shorter getting-started page is also available, with a different perspective.
TeX is a typesetting language. Instead of visually formatting your text, you enter your manuscript text intertwined with TeX commands in a plain text file. You then run TeX to produce formatted output, such as a PDF file. Thus, in contrast to standard word processors, your document is a separate file that does not pretend to be a representation of the final typeset output, and so can be easily edited and manipulated.
Here are a couple of links with further background:
If you are looking to install a complete system, we recommend installing TeX Live (Unix/GNU/Linux, macOS, Windows). MiKTeX is the most commonly-used alternative. Both distributions support all common platforms, are (almost entirely) free software, and can be downloaded and installed at no charge. See their home pages. (Other TeX implementations are also available.)
If you want physical discs, you can submit a request to the volunteers who have offered to burn them.
Here is a little of the principal TeX documentation available on the web. A longer list of documentation links is available.
LaTeX:
Other formats:
Fonts: a discussion of the fonts available for use with TeX is available separately.
General help: see below.
Since TeX predates the Internet, let alone the web, it has a long tradition of documentation being available in book form. (Not to mention being a typesetting program!) Here are the books we recommend most highly.
See these additional documentation links for many more books and other references.
If you have TeX installed and just want to get started, you can peruse and process this introductory LaTeX document (small2e). When you've mastered that, move on to this more complex example (sample2e).
The basic procedure is to create plain text files in any editor or GUI front end (TeXworks, TeXShop, GNU Emacs, etc.), and then run (for example) pdflatex myfile.tex from a command line to get PDF output. Or run latex to get DVI output.
Finding software and/or packages:
If you've tried everything and are still stuck, feel free to email the public support list.
Happy typesetting!