Binary Data Store in AEM

In AEM 6.x, binaries are by default chunked and stored in the Node data store – Segment (TarMK) or Document (MongoMK). Options provided to store binary data (>4kb) in a separate data store – file system or an S3 bucket. The separate datastore is preferred for production systems esp. asset deployments for performance and maintenance reasons.

Source: Configuring Node Stores and Data Stores in AEM 6 – docs.adobe.com