Data lake ingestion is simply the process of collecting or absorbing data into object storage such as Hadoop, Amazon S3, or Google Cloud Storage. For a streaming source, ingestion would usually be continuous, with each event or log stored soon after it is received in the stream processor. For batch data, ingestion might be periodical – i.e., a script that runs once a day to import new records in the CRM and write them to the lake as CSV or JSON files.