When you create a versa account, a smart contract gets deployed onto the network representing your account. The contract initially has a single device key, stored locally and used to sign transactions. Guards add an additional layer of security to your account, and they can be used to approve risky transactions and recover your account. You may also view these additional validators as Multi-factor Authentication for your account.
We recommend using a setup of your social accounts (easy access on a frequent basis), and trusted friends or family members as your account guards. Details of different types of guards can be found here: