Use sign into describe starting a session on a computer, a device, a network, anapp, or anywhere a username and password are required. Use sign out to refer to ending a session.
Don't use log in, login, log into, log on, logon, log onto, log off, log out, logout, sign into, signin, signoff,sign off, or sign on unless these terms appear in the UI (and you're writing instructions).
The verb form is two words, sign in or sign out. Avoid using as a noun or adjective (sign-in, sign-out). Instead, use a more descriptive or precise term.
Examples
Enter your password to sign in.
Learn how to sign in to Power BI service on the web and how to sign out of it.
After an extended period without activity, the network will sign you out automatically.
See also connect, single sign-on (SSO)
