Don't Panic: The Official Hitchhiker's Guide to the Galaxy Companion

Blurb

Don't Panic: The Official Hitchhiker's Guide to the Galaxy Companion is a book by Neil Gaiman about Douglas Adams and The Hitchhiker's Guide to the Galaxy. The book was originally published in January 1988 in the United States and United Kingdom.
A second edition, retitled Don't Panic: Douglas Adams & The Hitch Hiker's Guide to the Galaxy was published in the United Kingdom in July 1993, containing additional material by David K. Dickson.
A third edition, with another slight title revision was published in the UK by Titan Books in June 2002, and contains further additional material, this time by M. J. Simpson.
An updated edition was published by Titan Books in October 2003.