The Hitchhiker's Trilogy is a collection of the Hitch-hiker stories all in one. There are actually 5 books in one book here. The books are The Hitchhiker's Guide to the Galaxy, The Restaurant at the End of the Universe, Life, the Universe and Everything, So Long, and Thanks for all the Fish, and Mostly Harmless.
the story has about 5 main characters. One of which is a human from planet Earth named Arthur Dent. He is surprised one day (the day his house is to be demolished) that one of his friends is actually not from Earth and that the Earth is in fact scheduled to be demolition that day. This starts Arthur's crazy and sometimes hysterical and confusing journey through space and time travel. The one thing that is suppose to help him but doesn't seem to actual be much help is The Hitchhiker's Guide to the Galaxy which happens to have "DON'T PANIC" written on it.
For the most part this was an entertaining book. I wouldn't go on to say it is one of my favorites but it did have it's moments when I was laughing hysterically out loud. Most of those moments involved a robot who was deeply depressed.
The first three stories followed a pretty steady story line but the last 2 books were a bit different. They didn't seem to have the same feel or impact as the first three had.