In the 8th century, Charlemagne declared that 240 pennies or pfennigs should be minted from a pound of silver. A Carolingian pound was approximately 326 grams, so a single coin thus contained about 1.36 grams of silver. (Today, this amount of silver would cost about 40p sterling.)

The penny is among the lowest denomination of coins in circulation.

1/100 of the British pound sterling (see British one penny coin), the former Irish pound, the Gibraltar pound, the Falkland Islands pound, or a coin with that value: see history of the English penny.; 1/240 of the British pound sterling or Irish pound prior to February 15, 1971, of the Pound Scots prior to 1707, and also the pre-decimalisation currencies of Australia, New Zealand and South Africa (1/12 of the shilling), or a coin of that value.; The preferred name for the one-cent coin in the United States and in Canada, worth 1/100 of the dollar: see penny (U.S. coin), penny (Canadian coin).;

In addition, variants of the word penny, with which they share a common root, are or were the names of certain units of currency in non-English-speaking countries:

A fening is 1/100 of a Bosnia and Herzegovina convertible mark; A pfennig was 1/100 of a German mark; A penni was 1/100 of a Finnish markka;

In the United States and Canada, \"penny\" is normally used to refer to the coin; the quantity of money is a \"cent.\" Elsewhere in the English-speaking world, the plural of \"penny\" is \"pence\" when referring to a quantity of money and \"pennies\" when referring to a number of coins. Thus a coin worth five times as much as one penny is worth five pence, but \"five pennies\" means five coins, each of which is a penny.

When dealing with British or Irish (pound) money, amounts of the decimal \"new pence\" less than £1 may be suffixed with \"p\", as in 2p, 5p, 26p, 72p. Pre-1971 amounts of less than 1/- (one shilling) were denoted with a \"d\" which derived from the term \"denarius\", as in 2d, 6d, 10d. The lettering \"new penny\" or \"new pence\" was changed to \"one penny\", \"two pence\" or \"five pence\", etc. on British decimal coinage in 1982. Irish pound decimal coinage only used \"p\" to designate units (possibly as this sufficed for both the English word \"pence\", and Irish form \"pingin\").

The British penny as a unit of currency dates back well over a thousand years, and for most of that period the silver penny was the principal denomination in circulation.