Azure Data Lake Storage Gen2 is Azure's big-data lake storage built on Azure Blob Storage with a hierarchical namespace. Think "S3/GCS for Azure," plus folder-like semantics that Hadoop/Spark tools expect.
abfss://container@account.dfs.core.windows.net/lake/ raw/ bronze/ silver/ gold/
What Gen2 adds over plain blobs
- Hierarchical namespace (real directories/rename-friendly for analytics engines)
- Fine-grained ACLs on directories/files (POSIX-like) plus Azure RBAC
- Optimized for analytics workloads (Spark, Synapse, Databricks, HDInsight)
Fresher picture
Landing zone for ELT: dump raw files, then Spark/Databricks/Synapse SQL transform into curated layers. Same medallion idea as other clouds.
Interview tip: "ADLS Gen2 = Azure lake storage on Blob + hierarchical namespace." Mention abfss:// paths and that Databricks/Synapse read it natively.