Penny (English coin) in the context of British one penny coin (pre-decimal)
The Britishpre-decimalpenny was a denomination of sterling coinage worth 1⁄240 of one pound or 1⁄12 of one shilling. Its symbol was d, from the Roman denarius. It was a continuation of the earlier English penny, and in Scotland it had the same monetary value as one pre-1707 Scottish shilling, thus the English penny was called sgillin in Scottish Gaelic. The penny was originally minted in silver, but from the late 18th century it was minted in copper, and then after 1860 in bronze.
The plural of "penny" is "pence" (often added as an unstressed suffix) when referring to an amount of money, and "pennies" when referring to a number of coins. Thus 8d is eightpence or eight pence, but "eight pennies" means specifically eight individual penny coins.