What is a transaction hash? A simple explanation of transaction hash

What is a Transaction Hash?

A transaction hash, also known as a TXID, is a unique identifier assigned to every transaction made on a blockchain. It is a cryptographic fingerprint that serves as a tamper-proof record of the transaction's details.

How a Transaction Hash is Generated:

1. Transaction Inputs and Outputs: When a transaction is created, it includes information about the inputs (the addresses from which funds are being sent) and outputs (the addresses to which funds are being sent).
2. Merkle Tree: The transaction data is combined with other transactions in a block and hashed together using a Merkle tree. Each hash represents a node in the tree, and the root hash is at the top.
3. Final Hash: The root hash of the Merkle tree is then encrypted using a cryptographic hash function, such as SHA-256 or Keccak-256. The resulting hash is the transaction hash.

Purpose of a Transaction Hash:

• Uniqueness: Each transaction hash is unique, ensuring that transactions cannot be faked or duplicated.
• Verifiability: Anyone can verify the authenticity of a transaction by checking the transaction hash against the blockchain.
• Immutability: Once a transaction is included in a block and assigned a transaction hash, it cannot be altered or removed from the blockchain.
• Traceability: The transaction hash can be used to trace the movement of funds through the blockchain, enabling audits and investigations.

Example of a Transaction Hash:

A transaction hash typically looks like this: 0xabc123def4567890987654321fedcba987654321. It is a long string of hexadecimal characters that represents the cryptographic fingerprint of the transaction.

Conclusion:

A transaction hash is a crucial component of blockchain technology. It provides a unique and immutable record of every transaction, ensuring that the integrity and transparency of the blockchain are maintained. Understanding the concept of a transaction hash is essential for anyone interacting with blockchain-based applications.