Before decimalization, British money was a bit idiosyncratic. My familiarity is with what was in use in the sixties, not long before decimalization.
Starting from the pound and going down: 20 shillings = 1 pound, 12 pennies = 1 shilling (therefore 240 pennies = 1 pound).
That seems simple enough, just a slightly odd choice of breakdown. Prices and amounts were spoken as the number of shillings and pence, so something that was 1 shilling and 6 pence you said "one and six". Something of no account you said "wasn't worth tuppence", which was just a corruption of two pence. Bob was a common nickname for a shilling - something might be worth 5 bob, 5 shillings.
But then you have to be aware of the coins and banknotes that were in use. And that's where things go pear-shaped.
There were 1, 5, 10, and 20 pound notes. There were also ten shilling notes, ten bob notes. These were all different sizes and colors, not like American money. I don't know how blind people manage in America.
There was an old coin, the crown, worth 5 shillings. But it was obsolete, not used for spending, and rarely minted, just for collectors really. But there was a half crown coin, worth 2 shillings and 6 pence, that was in common use. There was a 2 shilling coin, also known as a florin. There was a shilling coin, and a small sixpence coin (about the same size as a dime). These were known as silver coins (not actually made of silver any more, but at least silvery-colored).
There was a 3 penny coin, known as a thrupenny bit, a weird chunky little coin, vaguely round but actually having a shape that was a polygon with multiple sides. It was a funny color, too.
There were pennies, and half-pennies (known as ha'pennies), and sometimes you even came across farthings, worth a quarter of a penny. These had pretty much fallen from use, simply because you couldn't buy anything for a farthing by then (I think you still could, if you look back to the thirties and forties, but inflation had done the farthing in). These were called coppers, not that they were made of copper, but they looked coppery-colored when new, brownish after some use.
At decimalization, in 1971, all these coins were retired except for the florin. With 1 pound = 100 new pence, the two shilling coins were valued at 10 pence. New 10 pence coins were minted, and the old florins were gradually taken out of circulation, over a period of years.