# `CDC` Overview

+ **`Change Data Capture (CDC)`** is a set of software design patterns used to determine and track the data that has changed so that action can be taken using the changed data
  + `CDC` simplifies the replication process and consumes fewer computation resources
  + `CDC` maintains timely data consistency 
+ **`Fan-out`** means deliver (or spread) a message to one or multiple destinations possibly in parallel, and not halting the process that executes the messaging to wait for any response to that message

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