When a transaction is made on a blockchain network, it is hashed and included in a block. Here's a step-by-step breakdown of the process:

1. Transaction creation: A user initiates a transaction, such as sending cryptocurrency to another user.

2. Transaction hashing: The transaction data is hashed using a hash function, like SHA-256, to create a unique digital fingerprint (transaction hash).

3. Transaction verification: The transaction is verified by nodes on the network to ensure its validity and integrity.

4. Block creation: A new block is created, and the transaction hash is included in the block.

5. Block hashing: The block's header is hashed to create a unique block hash.

6. Block verification: Nodes on the network verify the block hash and the transactions within.

7. Blockchain update: The new block is added to the blockchain, and the blockchain is updated.

By hashing transactions and including them in blocks, blockchain networks can:

- Ensure transaction integrity

- Prevent transaction tampering

- Enable efficient transaction verification

- Create a permanent and immutable record of transactions

This process is critical for the security and reliability of blockchain networks, and hash functions play a vital role in ensuring the integrity of transactions and the blockchain itself.