files begin with a command, \documentclass,
which tells what kind
of document follows. For instance, if you wanted to use the
article format of the AMS family of journals, and wanted to
include
some fancy AMS
math symbols and commutative diagrams, then type
\documentclass[11pt]{article}
\usepackage{amstex, amssymb, amscd}
...
Some other possibilities, instead
of article, are book, report and letter.
book or report might be good for a thesis.
See Chapter 2 in the most recent edition of Lamport's book for a description of the
various document classes available. The amstex package loads
most of the features of A
MS- while
amssymb
loads some extra math symbols, and amscd loads
some special commands for drawing commutative diagrams. Incidentally,
there exist many other specialized packages besides the above three
AMS packages which you can load into your document to extend the
functionality
of ; consult
The Companion for a complete list and full details.
An alternative
\documentclass command, which will produce output that is
closer to the format of AMS journals, is
\documentclass{amsart}
This document class automatically loads the amstex package, so no need
here for the \usepackage{amstex} command afterward.
The default in article is to use fonts 10 points high. (A point is
roughly 1/72 of an inch, which also incidentally is roughly the
resolution of a pixel on the monochrome monitors in the department.)
Since 10 points is a bit small for some eyes,
you may prefer to use 11 or 12 point fonts.
Everything you type and want printed must appear between the lines
\begin{document}
The text goes here ...
\end{document}
So the basic structure of your document might look like:
\documentclass[11pt]{article}
\usepackage{amstex}
\begin{document}
This is a very interesting and important paper....
(Rest of the paper)
\end{document}