CRDTs, or Conflict-free Replicated Data Types, are data structures that can be stored on different computers and allow for instant updates to each peer’s own state without the need for network requests. CRDTs are great for building collaborative apps without a central server. There are two types of CRDTs: state-based and operation-based. State-based CRDTs transmit their full state between peers, while operation-based CRDTs transmit only the actions taken by users. This post focuses on state-based CRDTs. An example of a state-based CRDT is the Last Write Wins Register, which holds a single value and overwrites its current value with the last value written. Another example is the Last Write Wins Map, which can hold multiple values and merges the states of individual registers.
https://jakelazaroff.com/words/an-interactive-intro-to-crdts/