Pre-Decimal Coins

For the majority of English (and eventually British) history, a pre-decimal monetary system based on pounds, shillings and pence was used. In this pre-decimal currency, one pound sterling was divided into twenty shillings, and one shilling into 12 pence. This meant there were 240 pennies to the pound.
Following decimalization, shillings were no longer used and the pound was instead equivalent to one hundred pennies.

he UK’s pre-decimal currency system is claimed to date from ancient Roman times. The Romans at that time used coins denominated in the Latin words librae, solidi and denarii. Similar to our eventual system, one Roman librae was divided into twenty solidi, and one solidi into twelve denarii. It was because of this that the pre-decimal currency was abbreviated to £sd or Lsd.

Source:  https://www.bullionbypost.co.uk/index/collectible-coins/pre-decimal-currency/