what I don't understand is how it all started. noone would buy something that has no value (the first mined coins). so who bought the first coins? It might have started as a pump and dump, and once this caused a valorization it caused a chain reaction.
Noone designed it as a pump and dump scheme. It was designed as a digital currency (as were all the digital currencies from the early 90's).
It was obvious that an exchange was needed to determine a price for it, but even before one became available, the first transaction occurred when a miner offered 10000BTC for a couple of pizzas. No pizza shop accepted them, so an aspiring bitcoin user paid fiat for the pizzas and made the trade to obtain his bitcoins. That determined the first defined price (about .2 cents). Interestingly, it wasn't zero before that really...it was undefined.
so one guy bought BTCs because of something like a joke, but how did the market build itself? who started to buy coins, and why?