It is fair to say that many of Adam's books contain the most ridiculous and far-fetched situations it seems possible to imagine; the plots are regularly interrupted as he goes off at ninety-degree tangents and his deeply unlikeable characters display some of the worst (non-human) traits imaginable. Because of this, and for a hundred other reasons, his books are truly brilliant.

"Comedy science fiction" is a brand all of Adam's own making and he may forever be the master of it. But his books are more than just comic offerings; Adams was a great observer of human behaviour and interaction. The stories work because there is actually a ring of truth in them - there are characters and situations we are all able to relate to no matter how "unreal" they are. There are many who simply do not understand the attraction of his bizarre writing. For these people the appeal is impossible to explain and it may be that they never really "get" Adams.

The Hitchhiker's Guide to the Galaxy made Adam's name when it started as a radio series in the late 1970s and was later turned into the book. But with sequels like the Restaurant at the End of the Universe and So Long, and Thanks for all the Fish he has created a library of works that has attracted a cult following. For fans collecting his work, first editions of Hitchhiker's Guide can realize up to $500; his other works costing less.

As a luminary in his field, Adams' death in 2001 was a genuine loss to literature. He offered the world something different with his writing. When many other authors played it safe with books which sold well, but were all variations on the same theme, Adams dared to be different. He put his personality on the page with every word he wrote and his books are all wonderfully rich and much-loved as a result.