The Bitcoin Blockchain ecosystem is actually quite a complex system due to its dual aims: that anyone should be able to write to The Bitcoin Blockchain; and that there shouldn’t be any centralized power or control. Relax these, and you don’t need many of the convoluted mechanisms of Bitcoin.
The Bitcoin Blockchain ecosystem acts like a network of replicated databases, each containing the same list of past Bitcoin transactions. Important members of the network are called validators or nodes which pass around transaction data (payment) and block data (additions to the ledger). Each validator independently checks the payment around. There are rules in place to make the network operate as intended
Bitcoin’s complexity comes from its aims. The aim of Bitcoin was to be decentralized, i.e. not have a point of control, and to be relatively anonymous. This has influenced how Bitcoin has developed. Not all blockchain ecosystems need to have the same mechanisms, especially if participants can be identified and trusted to behave.
Review the original whitepaper by Satoshi Nakamoto titled Bitcoin: A Peer-to-Peer Electronic Cash System
A gentle introduction to blockchain by Anthony Lewis
