What is ETL in data processing?

Updated May 15, 2026

Short answer

ETL stands for Extract, Transform, Load—a pipeline for moving and processing data.

Deep explanation

ETL extracts data from sources, transforms it into a structured format, and loads it into a target system like a data warehouse. It is widely used in analytics and business intelligence systems.

Real-world example

Loading data from CRM systems into a warehouse for reporting dashboards.

Common mistakes

Skipping transformation logic or loading unclean data.

Follow-up questions

What is ELT and how is it different?
When should ETL be used?

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