Cryptography is the branch of mathematics and computer science that deals with protecting information and proving where it came from. Cryptocurrencies take their name from it, because cryptography is what keeps them secure without a bank or other middleman.
How is cryptography used in crypto?
Two techniques matter most:
- Key pairs and digital signatures. Every wallet is built on a private keyPrivate keyA secret number that proves you own the crypto in your wallet. Whoever holds the private key controls the crypto. and a public keyPublic keyA key calculated from your private key that others use to verify your signatures, and that is safe to share. calculated from it. You sign a transaction with the private key, and anyone can check the signature with the public key. But nobody can work out the private key from the public key.
- Hash functions. A hash function turns data into a short fingerprint, called a HashHashA short fingerprint calculated from data, which changes completely if the data is altered by even a single character., which changes completely if the data changes by a single character. The blocks in a BlockchainBlockchainA public ledger where transactions are grouped into blocks, each linked to the one before, so past records can't be altered without it showing. are linked together with these fingerprints.
Think of a wax seal on an envelope. Everyone can see who sealed it and whether it has been broken, but nobody can forge the seal without the stamp.
Why does it matter?
Cryptography lets strangers trust transactions without having to trust each other. It is one reason nobody has managed to counterfeit bitcoin.
The weak link is rarely the mathematics. It is people. If someone gets hold of your private key or your seed phraseSeed phraseA list of 12 or 24 words that backs up every key in your wallet, so whoever has the words can restore the wallet and take the crypto., no cryptography can help you. That is why scammers try to trick people rather than break the cryptography.
Everything in Myntkaup Learn is written and regularly reviewed by the Myntkaup editorial team. It is for education and is not investment advice. Editorial policy. Updated 18 October 2026.