By hashing each chunk using SHA-256, a unique digital fingerprint (or hash value) is created for each chunk. This hash value has several important properties:

1. *Uniqueness*: Each chunk's hash value is unique, even if the chunks are similar or identical.

2. *Fixed size*: SHA-256 hash values are always 256 bits (32 bytes) long, regardless of the chunk size.

3. *Deterministic*: Given a specific chunk, the hash value will always be the same.

4. *Non-reversible*: It's computationally infeasible to recreate the original chunk from its hash value.

These properties make SHA-256 hash values ideal for identifying and deduplicating chunks:

1. *Duplicate detection*: By comparing hash values, identical chunks can be quickly identified and deduplicated.

2. *Efficient storage*: Only the hash value needs to be stored, reducing storage requirements.

3. *Fast lookup*: Hash values enable fast lookup and retrieval of chunks.

By using SHA-256 hashing, data chunking and deduplication become more efficient, secure, and reliable.