Currency lads and lasses

Currency lads and lasses are people from long ago whose job was to travel around exchanging coins for paper money. They were called currency lads and lasses because they carried a bunch of different kinds of coins or currency with them. They exchanged coins and paper money so that people could have the right kind of money to buy things with. People trusted the currency lads and lasses because they knew that they could always get the right kind of money they needed.