What does ETL stand for in data engineering?

• A. Encrypt, Transfer, Lease
• B. Extract, Transform, Load; process of moving data from sources into a data store
• C. Evaluate, Transport, Label
• D. Event, Trigger, Log

Answer: (B)

ETL stands for Extract, Transform, Load. It describes moving data from various source systems into a destination data store. First, extraction pulls data from sources in different formats with minimal impact on the source. Next, transformation cleans and reshapes the data—applying business rules, handling missing values, standardizing formats, joining datasets, and deriving new metrics. Finally, loading writes the prepared data into the target store, such as a data warehouse or data lake, ready for analysis and reporting. This sequence is the standard pattern used to make diverse data usable for decision-making. Other options describe unrelated activities like encryption, labeling, or event logging, which don’t capture this data movement and preparation flow.