Change Data Capture (CDC) is the method of developing ETL processes to propagate changes in the source system into your data warehouse for dimension tables.
CDC is directly related to another DWH concept of Slowly Changing Dimensions (SCD), the dimension tables that data changes constantly throughout the life of data warehouse.
A good example would be the
Employee dimension table, which holds data on the employees in your company. As you can imagine, this table is in constant flux: new employees are hired and some employees leave the company, change positions and roles, or even transfer between departments. All these changes have to be propagated to an
Employee dimension table in DWH from the source ...