The practice of keeping Bitcoin private keys completely offline using hardware devices like Jade, eliminating remote attack vectors while retaining the ability to sign transactions when needed.

A hardware wallet generates and stores private keys on a device that never connects to the internet. When spending is needed, wallet software like the Blockstream app constructs an unsigned transaction, passes it to the hardware device for signing, and receives only the signed result. The private key never leaves the device. Jade Plus extends this model with air-gapped QR code communication, maintaining complete physical separation from networked computers.

Cold storage prioritizes security over convenience, making it best suited for long-term holdings. For higher-value setups, it can be combined with multisignature (multisig) configurations where multiple devices stored in separate physical locations must cooperate to authorize a transaction, protecting against single-device theft or loss.