Your Bitcoin at Swan is stored offline in cold storage for increased security.
Bitcoin can either be stored in hot wallets or cold wallets. Hot wallets are connected to the internet so they can initiate transactions quickly, but as a result, they are exposed to more security risks from hackers and malware.
Cold wallets (also called cold-storage) are not connected to the internet directly. Their private keys are stored offline. As a result, transactions from these wallets can't be broadcast instantly and there are more security steps before transactions are broadcast. Overall, this cold storage system better protects your from hackers and malware.