What is the Schnorr scheme in cryptocurrencies?

The Schnorr scheme in cryptocurrencies is a special digital signature algorithm that determines the relationship between a private key (password) and a public key (address). Choosing the right signature algorithm is very important for maintaining the privacy, scalability, and security of the blockchain. The advantage of the Schnorr signature is that it is much easier to prove its security, so the scheme is especially often used for multi-signature transactions.