One of the major difference between fiat and Bitcoin is that the former is created (or printed) by a centralised entity while the latter is mined by a distributed network of computers.
Miners solve mathematical problems on special software in order to secure the network, and in exchange for a certain amount of Bitcoin as a reward for their work.
In the current financial system, floating currencies are regulated by central banks – they can inject or remove money via a centralised banking system. The amount of fiat money is uncapped as central banks have the power to print an unlimited supply.
The creation of Bitcoin is decentralised, transparent and follows an immutable mathematical formula. Bitcoins are not printed but "mined" by computers plugged on the network. As per the network's rule regarding Bitcoin's controlled supply, there will only be 21 million units ever mined.
Initially, Bitcoin’s price was indexed on the prerequisite costs needed to run the network.
Mining cryptocurrencies is a resource-draining activity that requires capital investment and operational expenditure.