Preface This is one of the three main &GAP; books. It describes most essential changes from previous &GAP; releases.

In addition to this manual, there is the &GAP; Tutorial (see ) and the &GAP; Reference Manual (see ) containing detailed documentation of the mathematical functionality of &GAP;.

A lot of the functionality of the system and a number of contributed extensions are provided as &GAP; packages, and each of these has its own manual. New versions of packages are released independently of &GAP; releases, and changes between package versions may be described in their documentation.