Cryptography

Cryptography is the science of securing information through encoding, making it readable only to those with the right decryption key. In blockchain technology, cryptography is foundational—it protects user data, secures transactions, and ensures the integrity of decentralized systems. Without cryptography, blockchains wouldn’t be trustless or tamper-resistant.

How Cryptography Works in Blockchain

Blockchain networks rely on two key forms of cryptography: hashing and asymmetric encryption. Hashing turns data into a fixed-length code (like SHA-256 in Bitcoin) that is irreversible, ensuring the data hasn’t been altered. Asymmetric encryption uses a public and private key pair—public keys are shared to receive funds, while private keys are kept secret to sign transactions.

Cryptography in Action

When you send crypto, your private key signs the transaction cryptographically. The network can then verify the signature using your public key without ever exposing your private key. Cryptographic techniques also ensure blocks are chained together in a secure, immutable ledger.

Why It Powers Blockchain Security

Cryptography keeps blockchains decentralized, secure, and resistant to fraud. It ensures only valid transactions are added and prevents double-spending or unauthorized access to digital assets.