system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Where do currency symbols come from?

I guess with the Euro Symbol it's easier because of its relatively recent introduction, but still: I unterstand the "E", but why two horizontal lines? 
Much more of an enigma is the Dollar sign to me. Nowhere in the word appears an "S", and even in the original "Taler" there's no "S". And again the two lines. Can someone enlighten me?
gpt
The pound sign, £, is a stylized capital letter "L". It stands for "Libra", which is Latin for "pound", in the sense of weight. The British pound [in sense of currency] used to be defined as a pound [in the sense of weight] of sterling silver. Hence why the British currency is often referred to as Sterling.