UserOperation is a new type of data structure that can be sent to a special mempool called the alt-mempool on behalf of a user. Much more efficient and flexible than a typical transaction.
Day by day, slow and steady, account abstraction is gaining more popularity, and I feel like an overly enthusiastic anime girl witnessing the conversations about AA online and IRL.
Account abstraction is a concept that allows developers to separate the control of a user's funds from the execution of smart contract code.