system
Given the following post, respond as if you're commenting on Reddit:
human
How did England transition from old English currency to new English currency? (Eg tuppence and sixpence to pounds and pence)
gpt
1971.

Tuppence and sixpence are simply shortened versions of "Two pence" and "Six pence", which is why you will sometimes hear them spoken today.

Pre-decimalisation there was still pounds and pence, but the values were broken down differently. At the top was the pound, in a pound was 20 shillings, and in each shilling was 12 pence. That's 240 pence to the pound. Since a shilling was 12 pence, a half shilling was 6 pence, hence the common "sixpence".

In 1971 they decided that it would be simpler to use 100 pence to each pound.