How Conflict-free Replicated Data Types power active-active database replication

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Introduces Conflict-free Replicated Data Types (CRDTs) as a solution for active-active database replication, detailing how their built-in merge rules resolve concurrent updates automatically. Contrasts CRDTs with Last Write Wins (LWW) and synchronous consensus protocols, explaining the trade-offs in write latency, availability, and data integrity. Provides a concrete example of inventory management to demonstrate how CRDTs signal inconsistencies (e.g., negative counts) instead of silently losing data, enabling better application-level handling of overselling. Mentions that Redis Cloud and Redis Software implement CRDT semantics for several data types to support active-active geo-distribution.