Extract, Transform, Load - process of moving data from various sources to a data warehouse. Like sorting, cleaning, and organizing items from different stores into one organized warehouse.
Companies use ETL to combine sales data from different regions into a single database for analysis.
All four are managed data integration services used to build ETL/ELT pipelines: connect to sources, transform data, and load it into analytics stores (e.g., data warehouses/lakes). AWS Glue is Spark-based with a Data Catalog; Azure Data Factory is orchestration-first with mapping data flows; Cloud Data Fusion is a managed CDAP-based visual pipeline builder; OCI Data Integration provides visual design, scheduling, and lineage for Oracle Cloud targets.