A package is a body of Macaulay 2 source code devoted to a particular topic. Many packages are distributed with Macaulay 2, and others are available from various users on the internet.
For more detailed information about packages, see
Package.
To load a package, say FirstPackage, use
loadPackage or
needsPackage, as in:
loadPackage "FirstPackage"
or
needsPackage "FirstPackage"
Macaulay 2 searches for the file FirstPackage.m2 on your search
path. The packages provided with Macaulay 2 are on your search path, as is your current working directory.
Documentation for the packages provided with Macaulay 2 is already installed. TO install documentation for another package, use
installPackage.
installPackage FirstPackage
You may see what packages have been loaded with the variable
loadedPackages.
loadedPackages