Using "cold storage" for digital assets means keeping keys offline (disconnected from the internet) to reduce the risk of theft.
Since the majority of cryptocurrency theft is a result of keys stored online (i.e., in a "hot wallet"), keeping them offline until they are ready to be sent is an excellent strategy to increase your security.
Ways to keep your keys in cold storage include using an offline-generated address, a hardware device, or multisig wallets like Casa's 3-key and 5-key vaults.
