Vault items have four different types. Every type has its data structure.
Username and Password
A username and password is a basic Username and Password type. It also contains three different subtypes. Local User is just a Username, Password, and Resource to assign, Domain User additionally has Domain name information, and Vault User is a basic Username and Password.
Public-Private Key Infrastructure keeps your Private Key, Username, and Passphrase. You can also use this information to connect your SSH resources.
Secret text is basic plain text information to keep in a secure storage.
This option allows users to use their username and password to connect any resource.