WHAT EVERY DEVELOPER SHOULD KNOW ABOUT CACHE COHERENCE

Summary from the TLDR Web Dev newsletter

Cache coherence makes sure that data stays consistent across multiple caches in distributed systems. There are two types of cache coherence protocols: snooping and directory-based protocols. In snooping protocols, caches "listen" on a bus, updating or invalidating copies based on other caches' actions. In directory-based protocols, a central directory tracks data location and state, coordinating updates and invalidations.