AMS-TeX

AMS-LaTeX is a collection of LaTeX document classes and packages developed for the American Mathematical Society (AMS). Its additions to LaTeX include the typesetting of multi-line and other mathematical statements, document classes, and fonts containing numerous mathematical symbols.

It has largely superseded the plain TeX macro package AMS-TeX. AMS-TeX was originally written by Michael Spivak, and was used by the AMS from 1983 to 1985.

The following code of the LaTeX2e produces the AMS-LaTeX logo ():

The package has a suite of facilities to format multi-line equations. For example, the following code,

causes the equals signs in the two lines to be aligned with one another, like this:

AMS-LaTeX also includes many flexible commands for formatting and numbering theorems, lemmas, etc. For example, one may use the environment theorem

to generate

Theorem (Pythagoras) Suppose ${\displaystyle a\leq b\leq c}$ are the side-lengths of a right triangle.
Then ${\displaystyle a^{2}+b^{2}=c^{2}}$.
Proof. . . □

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