https://lh3.googleusercontent.com/uDY7grpD1Za_Twas4NuU3L0pB7YRfQjUX20AHzRUVU5jjOFDYiJcHWQCDiG0xVb6qyxArQVuf9NAcJ9bkkHcDZXWTLS4aYtip2aGcPCtNQPTvV7HD06dTb9DpQgG6qz8PX6nlzEd
Blockchain (also called Distributed Ledger Technology (DLT)), makes the history of any digital asset transparent & unalterable through the use of decentralization and cryptographic hashing. One analogy to understand blockchain in a simple way is this Notion Doc. This Doc is shared with hundreds of people, everyone can access it at the same time and real-time changes are completely transparent.
The whole point of using a blockchain is to let people — in particular, people who don't trust one another — share valuable data in a secure, tamperproof way.
Each chain consists of several blocks and every new transaction is recorded on the block. The blocks are connected to each other and form a “chronological” data chain. The blocks confirm the exact sequence of transactions and are linked to each other securely. By adding additional blocks, the chain is getting even more verified/securer - the blockchain is immutable.
But who creates the block(s)? Blockchain networks consist of node operators, developers, miners and users who all contribute to the ecosystem. In general the blockchain is mainly maintained by “miners” who create new blocks based on a joint consensus. To make it simple - the parties vote on how to create the next block and the group with the biggest support wins.