CoachSelf-custody is holding crypto assets under private keys the owner controls, rather than as a balance at a venue or custodian. A hot wallet is one whose keys are on internet-connected systems, able to sign at once; a cold wallet is one whose keys are kept offline, so that signing requires a deliberate offline process. Multi-party computation (MPC) is a cryptographic method by which several parties, each holding a share of a key, jointly produce a signature without the key ever existing in one place.
