Am-utils includes an updated version of Amd, the popular BSD automounter. An automounter is a program which maintains a cache of mounted filesystems. Filesystems are mounted when they are first referenced by the user and unmounted after a certain period of inactivity. Amd supports a variety of filesystems, including NFS, UFS, CD-ROMS and local drives.

You should install am-utils if you need a program for automatically mounting and unmounting filesystems.