Coinbase wallet is a digital wallet that enables users to send and receive bitcoin, ether, and litecoin. But it does not store your private keys so you are essentially trusting Coinbase to keep your funds secure.
What is Vault?
Vault is an advanced version of Coinbase wallet which provides advanced security for storing large amounts of cryptocurrency offline, meaning that they are not susceptible to potential hacking attempts or cyber-attacks of any kind. If someone gains access to your computer who manages to get into your vault, they will not be able to steal your funds because they are stored safely offline on the device itself.
The main difference between Coinbase wallet and Vault is the types of cryptoasset storage they provide. Wallet ensures that you can access your funds on demand while Vault provides more security but requires you to take additional steps before accessing your funds.