Many programs come with some sort of documentation, often in a file called
README or something similar. It is a VERY good idea to read them with
care. It is boring to see (and answer) questions that are answered in
the documentation. Most programs also have ``man pages''; use the command
man programname to get documentation on a program named
programname. To get help using the man program, use
man man.
Most distributions put other documentation about programs in the directory /usr/doc/; your distribution should include documentation on how to access that documentation.