Can you explain what is meant by the term User Manager?

User Manager is a component or module in an application responsible for managing users. It typically includes functionality for creating, updating, deleting users, as well as managing their permissions and authentication.

In the context of Golang, it can be a structure with methods for working with users, for example:

type User struct {
    ID    int
    Name  string
    Email string
}

type UserManager struct {
    users map[int]User
}

func (um *UserManager) AddUser(u User) {
    um.users[u.ID] = u
}

func (um *UserManager) GetUser(id int) (User, bool) {
    u, ok := um.users[id]
    return u, ok
}

// and other methods for updating, deleting, etc.

Thus, User Manager centralizes the logic for working with users, making it easier to support and extend functionality.