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SHA-256

SHA-256 is a cryptographic hash function.

SHA-256 is a cryptographic hash function. A cryptographic hash function has a few key properties. It takes an input, called a preimage, and produces an output of a fixed length—all SHA-256 outputs are 256 bits long.

This process is deterministic, meaning a given input will produce the exact same output every time. Hash functions are also unpredictable: the slightest change to an input yields an entirely different output, such that it is infeasible to craft a desired output or calculate an input based on the outputs. SHA-256 is a member of a family of hash functions called Secure Hashing Algorithm (SHA) functions.

The Bitcoin protocol uses SHA-256 to derive transaction IDs (txids), block hashes, addresses, and Merkle trees. Occasionally, SHA-256 is applied twice, as in the case of txids.

SHA-256 is a cryptographic or data encoding concept that underpins Bitcoin's security and data integrity. Onramp's Bitcoin glossary explains SHA-256 and other cryptographic foundations to help investors understand the technology securing their digital assets.

Frequently Asked Questions

What is SHA-256?

SHA-256 is a cryptographic or encoding standard used in computer science and digital security. In Bitcoin, it plays a role in securing transactions, keys, or data structures.

Why is SHA-256 important for Bitcoin?

SHA-256 contributes to Bitcoin's security model by ensuring data integrity and authenticity. Cryptographic foundations like SHA-256 make Bitcoin's $1+ trillion network resistant to fraud and tampering.

Does Onramp leverage SHA-256 for security?

Onramp's infrastructure relies on proven cryptographic standards including concepts related to SHA-256. Onramp's multi-institution custody ensures that client Bitcoin is protected by multiple layers of cryptographic security.

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