Credit

A credit was a generic term for a monetary unit. Many worlds and civilisations described their money with the term. While they were not the same system, they often (but not always) referred to a currency system that operated electronically, rather than using currency (i.e., notes and coins).

Human usage

 * In the year 2050 credits (sometimes called "creds") were the currency in Department-controlled Britain. (TV: The Custodians, Oroborus) By 2062 the UK no longer used credits and had switched to the Euro. (PROSE: The Last Dodo)
 * In the 42nd century, in the Second Great and Bountiful Human Empire, the price of an Ood slave was 50 credits. (TV: Planet of the Ood)
 * In the year 200,000, a Kronkburger onboard Satellite Five cost 2 credits 20. A Head Chip costed 100 credits and a full Infospike costed 10 000 credits. (TV: The Long Game)
 * On New Earth, in 5,000,000,053, one patch of Forget 43 cost two credits. (TV: Gridlock)

Other species

 * The Stoish civilisation had credits which were stored on "Credit Cards'". The Tenth Doctor said that £1,000,000 was equal to 50,000,056 credits in the early 21st century, meaning that the average Sto credit was roughly equivalent to 2 pence or 3 cents. (TV: Voyage of the Damned)
 * The Inter Minorians and Lurmans used credit bars that were blue. One bar represented one credit. (TV: Carnival of Monsters)