ETL or Extract, Transform, Load is a type of data integration process that extracts data from different sources, transforms data into compatible formats, and loads it into a database to provide users with a unified, consistent data view. The process of ETL occurs before the data is stored in a data warehouse. So data integration is the overall process, and ETL is one of its types or methods. There are other methods of achieving data integration, like ELT (Extract, Load, Transform), data replication, data virtualization, streaming data integration, etc. However, ETL is one of the most popular methods and forms a critical step in supporting enterprise reporting and advanced enterprise analytics.