Rerun van Pelt is the name of Linus and Lucy's younger brother in the comic strip Peanuts.
Fred "Rerun" Stubbs was a character played by Fred Berry on the 1970s television show What's Happening!!.
A rerun (or sometimes, repeat) is a re-airing of an episode of a television program. The invention of the rerun is generally credited to Desi Arnaz. Some viewers find reruns annoying, although many views appreciate the opportunity to re-watch a programme they enjoyed or watch one they missed the first time round. There are two types of reruns, those that occur during a hiatus, and those that occur when a program is syndicated.
In the UK, the word "rerun" is rarely used, instead "repeat" is the more common term. "Repeat" is also used to for programmes shown less than a week after the original broadcast, before the next episode of the series.
In the USA, most episodic television shows run only during a certain season. In the northern hemisphere, this season is normally from early September until late May. In the summer (and sometimes around the holidays) shows stop filming. No more episodes are being produced, so the network airs previous episodes in their stead.
When a television program becomes popular, it often goes into syndication. This is when many episodes of the program are sold as a package for a large sum of money. Generally the buyer is either a cable company or a host of local television stations. Often, programs are not economical until they are sold for syndication. Unfortunately since local television stations often need to sell more commercial airtime than network affiliates, syndicated shows are usually cut to make room for extra commercials.
In the United Kingdom, most drama and comedy series run for shorter seasons - typically 6, 7 or 13 episodes - and are then replaced by others. An exception is soap operas with are either on all year round (for example EastEnders and Coronation Street), or are on for a season similar to the American system.
As in the US, fewer new episodes are made in summer. Until recently it was also common practice for the BBC, ITV and Channel 4 to repeat classic shows from their archives, but this has more or less dried up in favour of newer (and cheaper) formats like reality shows, except on the BBC where older BBC shows, especially sitcoms like Dad's Army and Fawlty Towers, are frequently repeated.
Syndication did not exist in Britain until the arrival of satellite, cable and later digital television from 1989 on. Nowadays the UK has many channels (for example UKTV Gold) which repackage and rebroadcast "classic" programming from both sides of the Atlantic. Some of these channels, like their US counterparts, make commercial timing cuts; others get around this by running shows in longer time slots, and critics of timing cuts see no reason why all channels should not do the same.