Login 登入
（重定向自Logoff）
In computer security, logging in, (or logging on or signing in or signing on), is the process by which an individual gains access to a computer system by identifying and authenticating themselves. The user credentials are typically some form of "username" and a matching "password", and these credentials themselves are sometimes referred to as a login, (or a logon or a sign in or a sign on). In practice, modern secure systems also often require a second factor for extra security.