Bitcoin is often described as the 'first cryptocurrency' in media, but I vaguely remember there was some history before Satoshi's (amazing) implementation.
I remember hashcash (not a currency) which was used to prevent spam way before Bitcoin, and Bitcoin uses its idea.
What were the other attempts at cryptocurrencies or precursors before Bitcoin?
You can find here a very long and detailed essay of mine, describing all Bitcoin's ancestors:
Bitcoin: The dream of Cypherpunks, libertarians and crypto-anarchists. On the second page of posts you can also find
a comparison made by me for Bitcoin and all of its ancestors. It was "hand made" to say so, but I think the article can help you understand better all you asked for.