What is ETL (Extract, Transform, Load)?

How it works

ETL pipelines are the backbone of data operations. The extract phase pulls raw data from APIs, databases, files, or SaaS tools. The transform phase cleans, normalizes, deduplicates, and restructures that data. The load phase writes the processed data to a target system. Modern ELT (Extract, Load, Transform) reverses the last two steps by loading raw data first and transforming it inside the warehouse using tools like dbt. Automation platforms like n8n and Make can handle ETL for small to mid-scale data flows, while dedicated tools like Fivetran or Airbyte handle larger volumes.