Data synchronization moves changes between databases, applications, warehouses, and services so each system has an appropriate current view. It must account for different update schedules, formats, ownership rules, and partial failures.
Reliable synchronization uses stable identifiers, version or timestamp evidence, idempotent operations, conflict handling, and retry controls. It does not treat one missing or delayed observation as proof that durable data should be removed.
ELI5
Data synchronization keeps related information consistent across different systems by carrying changes from one place to another. It needs rules for which source owns each field and what happens when updates arrive late or conflict.
For example, a changed customer address may need to reach a billing system and a support system. If one service is temporarily unavailable, a reliable sync retries safely and preserves the last known-good record instead of treating the missing response as permission to delete it.
