Hitchhikers Guide to the Galaxy is the story of a man. A man who's home has been destroyed to make way for a bypass, whose best friend is from somewhere in the vicinity of Betelgeuse, a man floundering to find his place in an ever expanding universe. It's also the story of a book.
Arthur Dent is a man who lives a very normal life. He wakes one morning to find that his home is being destroyed to make way for a bypass. So he does what any sane Englishman would do and lays down in front of a bulldozer. His day just gets worse from here. As it turns out his entire planet is slated for destruction to make way for a hyperspace bypass.
Enter Ford Prefect, an alien who initially thought that automobiles were the dominant life-form on planet earth, who came to earth to write up a blurb about the planet for the Hitchhikers Guide to the Galaxy. Ford is a Hitchhiker who gallivants about the Galaxy looking for a good time, and occasionally sends informational articles to be edited to pieces and uploaded to the most informational book in the universe. He saves Arthur from being destroyed along with the Earth by giving him a pint of bitters and sticking his thumb out to hitch onto a passing space ship. Which unfortunately is the ship currently destroying the Earth.
Then there is the book itself. The Hitchhikers Guide to the Galaxy. This is a book that will give you information about anywhere in the galaxy you want to go: where to get a good drink, what the proper grammar is when traversing time, what planets have the best parties, what races have the worse poetry. Most useful of all though is the fact that the best advice it can give is in big bold letters printed on the very front of the book. Don't panic.
But beyond the destruction of Earth, which is really just a slam bang hook to keep you reading. It's the story of the search for the question to life, the universe, and everything, and what people will do to find it. It's the story of what people do when they are faced with things they don't understand and don't have any frame of reference to, and what they do to adapt. In some cases it's have a nice drink and go with the flow. In some case it's to gibber wildly and grasp at straws. It's a look at the ridiculousness of life and how people react to it.
Don't get me wrong this is in no way a serious look at any of these things. This book is British comedy gold, but what keeps me coming back to it about once a year (besides the fact that it makes me laugh out loud) is the way Douglas Adams looks at the galaxy through the eyes of such a normal man, who has every reason to panic, and places him in such a ridiculous situation that really he has no choice to, and instead of giving him support characters that will coddle him and make him feel better they just tell him to go with it. Have a nice drink, everything will be cool and froody.
So I recommend you pick up this book, have a nice cup of tea, and laugh until you cry. The universe is a big big place, is full of ridiculous things, and isn't really what you expect of it at all. Know that you have a guide that you can look to that will explain all that you really need to know about whatever planet you end up on. Most importantly try to enjoy yourself and Don't Panic.