lfs-book/appendixa/file-desc.sgml

<sect2>
<title>Contents</title>

<para>
The File package contains the file program.
</para>

</sect2>

<sect2><title>Description</title>

<para>
File tests each specified file in an attempt to classify it. There are 
three sets  of  tests,  performed in this order: filesystem tests, 
magic number tests, and language tests. The first test that succeeds 
causes the file type to be printed.
</para>

</sect2>