What is Crypto Wallet?

Despite the name, a crypto wallet does not hold cryptocurrency in the way a physical wallet holds cash. Digital assets exist on the blockchain itself. What a wallet stores are the private keys — secret cryptographic codes — that authorize transactions from a specific address. Whoever controls the private key controls the funds at the associated address.

Wallets come in several forms:

• Software wallets (hot wallets): Applications on a phone or computer that remain connected to the internet. Convenient for frequent transactions but more exposed to online threats.
• Hardware wallets (cold storage): Physical devices that store private keys offline, signing transactions internally without exposing keys to an internet-connected machine. Examples include Ledger and Trezor devices.
• Paper wallets: A printed or written record of a key pair. Secure from online attack but vulnerable to physical loss or damage.
• Custodial wallets: Provided by exchanges or services that hold keys on the user’s behalf. Convenient but the user does not directly control the keys.

A wallet generates a seed phrase (also called a recovery phrase) — typically 12 or 24 randomly selected words — that can reconstruct the private key if a device is lost. Protecting this phrase is critical; anyone who obtains it gains full access to the wallet’s funds.

The phrase “not your keys, not your coins” is widely used in the crypto space to emphasize the importance of self-custody over relying on third parties to hold private keys.