Definition
A backup is a recoverable copy of essential information. For a wallet, that may include a recovery phrase, an encrypted key file, multiple recovery shares or configuration data. Different wallet designs require different materials. A screenshot of the balance or a public address alone usually does not provide the authority needed to spend assets.
How It Works
A useful backup must be readable, complete and compatible with a recovery method. If a wallet uses an additional passphrase, multisignature configuration or specific derivation information, those requirements must also be accounted for. Encryption protects confidentiality only if the decryption secret is available when needed. Keeping several copies can improve resilience to physical damage, but each copy also creates another place where sensitive information might be stolen.
Key Considerations
Test recovery through the wallet’s trusted procedure without disclosing secrets to unfamiliar software. Store backups where theft, fire and accidental loss have been considered, and avoid keeping every required item in the same vulnerable location. Updating an application does not necessarily require changing the backup, while changing keys or recovery configuration may do so. A backup restores access; it does not reverse a fraudulent transfer or invalidate a copy already held by an attacker.