What is a subnet in the crypto world?

The Avalanche crypto ecosystem allows the creation of subnets: let’s see what a subnet is and how it works. Avalanche subnets are sovereign networks with their own rules, composed of a dynamic subset of Avalanche validators.  Each subnet can have many blockchains, but each individual blockchain is validated only by a single subnet. A validator in turn can be a member of several subnets, but all subnet validators must also validate the primary Avalanche network. Subnets were introduced to be able to be independent, that is, with their own execution logic that does not depend on the primary network. In