Asymmetric keys is the use of two distinct or separate public and private keys (keys are different and not same as is the case with Symmetric keys). Public key is used for encryption and this can be decrypted only by a private key.

Public and Private keys are mathematically connected with each other and their relationship differs from one algorithm to another. These keys in cryptocurrencies ensure that transaction sources are legitimate and hackers cannot steal the funds.

In Bitcoin, the wallet address is a hashed version of the corresponding public key. It proves the ownership of address to receive funds / tokens / coins.