
Doubts have been raised over the future of Countdown after Carol Vorderman and Des O'Connor both announced they are quitting the programme. The news is likely to cause concern to the legions of fans who have watched the Channel 4 show since it first came on screen 26 years ago.
We take a look back at the history of the show and its stars.
:: Beginnings
Countdown is based on the French game show Des Chiffres et Des Lettres (Numbers and Letters), created by Armand Jammot. Belgian businessman Marcel Stellman brought the show to Britain, where it was originally aired by Yorkshire Television as Calendar Countdown before Channel 4 purchased the format ahead of its launch in 1982.
Countdown was the first show to appear on Channel 4 when the station went on air, and the show's then host Richard Whiteley was the first person to appear on the channel.
With its blend of word games and number-crunching, the programme has remained a stalwart of the afternoon TV schedule ever since.
:: Hosts
Richard Whiteley hosted the show from its first episode until his death from pneumonia in June 2005. The show was taken off the air following Richard's death, but reappeared in October 2005 with Des Lynam taking on the role of lead presenter.
Des quit the show in December 2006 and was replaced by Des O'Connor, who announced last week that he was leaving to return to the live stage.
Mensa member and numbers expert Carol Vorderman has been co-presenting Countdown since 1982. The mathematical expertise she displayed on the show has led to numerous appearances on science and educational programmes. She has also sold millions of sudoku books worldwide.
:: Memorable contestants
The most successful Countdown contestant was Harvey Freeman, who remained undefeated after nineteen games.
The youngest contestant was eight-year-old James Squire in 1992, and the oldest was Bertha Bourne, who appeared on the show in 1993 at the age of 87.
In 1998, Celebrity Countdown saw sixteen famous faces compete in a special weekly edition. Celebrities taking part included Siân Lloyd, Hugh Fearnley-Whittingstall and Jilly Goolden.
:: Fans
The programme has a wide fan base, with viewers of all ages tuning in.
Countdown has acquired a significant following among students and young people. Social networking website Facebook has several groups dedicated to the show, including the Countdown Appreciation group and an Ultimate Countdown Drinking Game group.
:: Outtakes
The letters game on Countdown has produced a number of memorable outtakes, most notably in the 1990s when both contestants came up with the work w*****s. The word was cut out of the programme but has since been aired on a number of 'bloopers' shows. Carol has also been reduced to giggles when asked to pull out consonants and vowels which happen to spell out rude words.
:: Awards
Countdown was voted Channel 4's Best Show of All Time by viewers in a 2003 Radio Times poll. The show was also honoured in July 2004 with a House of Commons reception in recognition of the series' contribution to promoting literacy and numeracy.