DagPB (DAG-Protocol Buffers) is one of the earliest and most common data formats used in IPFS to represent nodes in a Merkle Directed Acyclic Graph (Merkle-DAG).

Each DagPB node contains:

Data — a raw byte payload (often a file chunk).

Links — references (CIDs) to other nodes.

DagPB is compact, binary-encoded using Protocol Buffers, and primarily used for files and directories in IPFS’s UnixFS layer. Because it encodes minimal metadata, many DagPB blobs appear “blank” in higher-level indexes — they are simply content chunks or structural links, not rich semantic objects.

IPLD Docs about DagPB: https://ipld.io/docs/codecs/known/dag-pb.