A seed phrase (also called a recovery phrase or mnemonic phrase) is a sequence of 12 to 24 randomly generated words that serves as the master backup for a cryptocurrency wallet. From this single phrase, all private keys and addresses associated with the wallet can be regenerated. If a user loses access to their device, the seed phrase allows them to restore their wallet and funds on any compatible software. It should be stored securely offline, as anyone with the seed phrase has full access to the wallet.