By Caroline Westbrook
BBC News Entertainment reporter
With the film of The Hitchhiker's Guide To The Galaxy released on 28 April, Douglas Adams' series of cult books is once again in the spotlight.
Alan Rickman voices the robot Marvin the paranoid android
But while fans will no doubt jump at the chance to see the latest recreation of Adams' work, many cinemagoers are likely to be new to the whole Hitchhiker's phenomenon - either because they never watched or read it the first time around, or because they're too young to remember it.
So if you're a newcomer to the series, just what do you need to know?
The Hitchhiker's Guide to The Galaxy focuses on Arthur Dent, who is attempting to stop a bypass from being built through the centre of his house at the same time as alien race the Vogons are getting ready to build one right through the centre of Earth, thus destroying it.
However, Arthur escapes from Earth seconds before it is blown to smithereens by hitching a lift with his friend Ford Prefect, who is actually an intergalactic traveller from the planet Betelgeuse.
Martin Freeman plays Arthur Dent in the new film
After a close encounter with the Vogons that sees them being thrown into the depths of space, they are rescued by the Heart of Gold, a ship carrying two-headed galactic president Zaphod Beeblebrox, his travelling companion Trillian, and permanently depressed robot Marvin the Paranoid Android.
From there, the pair go on a whole series of adventures through space, many of which are focused around the answer to the question of Life, The Universe and Everything.
According to Deep Thought, the computer built for the very purpose of pondering the question, the answer is 42.
The actual Hitchhiker's Guide of the title is an intergalactic travel guide (whose writers include Ford Prefect), which tells you anything you need to know about wherever you happen to be in the universe.
Extracts are included at regular intervals in the radio series, TV series and the film; the latter two feature graphics from the guide complete with voiceover.
The guide includes definitions of everything from weird and wonderful alien races and habits through to more down-to-earth pursuits such as tea-drinking and poetry.
As for Earth itself, the guide describes it as "mostly harmless".
In the radio and TV show, Peter Jones was the voice of the guide - in the film the role is taken by Stephen Fry.
Douglas Adams claimed to have come up with the idea for the Hitchhiker's Guide in 1971, when he was 18, while lying drunk in a field in Innsbruck, Austria.
In 1977 he teamed up with producer Simon Brett to turn the idea into a reality.
Originally conceived as a radio show in which Earth was destroyed in a different way at the end of each episode, it gradually evolved into its better-known form and got the green light in August 1977 after a pilot episode had been made.
The TV show starred David Dixon as Ford and Simon Jones as Arthur
The first series was broadcast on BBC Radio 4 with little fanfare.
However, it soon gained a cult following and made the switch to the small screen in 1981, with Simon Jones playing the lead role of Arthur Dent.
Soon after the success of the first radio series, Adams was approached about turning the series into a book, which became a best-seller.
Adams subsequently continued the story in a number of sequels, The Restaurant At The End Of The Universe, Life The Universe And Everything and So Long And Thanks For All The Fish.
The final book in the series, Mostly Harmless, was published in 1992.
Surviving cast members reprised their roles on Radio 4 last year in the six-part adaptation of Adams' third Hitchhiker book, Life The Universe And Everything.
Adam's fourth book, So Long and Thanks For All the Fish, and his fifth novel, Mostly Harmless, have been adapted for an eight-part Radio 4 series, to be broadcast next month.
Adams was working on the script for the Hitchhiker's film at the time of his death, having spent years trying to persuade Hollywood to turn it into a movie.
In the 1980s he sold the concept to Columbia Pictures and moved to Hollywood to work on it with Ghostbusters director Ivan Reitman, but the pair were unable to agree on the screenplay.
Sam Rockwell (left) plays Zaphod Beeblebrox in the film
Disney bought the rights to the book in 1998 and Austin Powers' director Jay Roach was lined up to direct, with Jim Carrey tipped to play Arthur Dent.
However the project stalled once again, this time over budgetary problems.
The current version was produced by British company Hammer and Tongs.
Garth Jennings, one of the founder members of the company, makes his directorial debut on the film.
It remains true to the spirit of the book, although there are a few changes, including the introduction of a new bad guy, Humma Kavula, played by John Malkovich.