Copyeditors largely agree that when one is accessing a computer system or program that requires credentials, the proper verbs are the two-word phrasal verbs log in or log on. But when these phrases are not verbs, writers and editors are faced with a choice: Should the words be hyphenated or run together?
And is there a difference between logging in and logging on?
To Hyphenate or Not to Hyphenate
There is a clear line here between the two primary style guides and their official dictionaries:
- Merriam-Webster’s Dictionary (online), the preferred dictionary of the Chicago University Press, lists only the hyphenated log-in and log-on as noun forms.
- The AP Stylebook, whose preference is the Webster’s New World College Dictionary, prefers the closed compounds login and logon (and also includes logoff).
- As a possible tie-breaker, the American Heritage Dictionary (online) agrees with the Associated Press on the closed compounds login and logon.
So that’s two for login/logon and one for log-in/log-on. It’s still pretty close.
What Do the Computer People Say?
So what do you do when dictionaries disagree? You find another authority.
One place to look for a higher authority is within the industry where the words are most used. You might not have heard of it, but The Microsoft Manual of Style exists. It’s currently in its fourth edition, which was published at the beginning of 2012 in, you guessed it, Redmond, Washington. On page 329 of the MMoS, we find an entry which promises to clear things up, but really doesn’t.
The relevant direction is there: “The verb form is two words, log on or log off. As a noun or adjective, use one word, no hyphen.”
So there’s one more “vote” for the closed compound. But wait! Before we get to that part, we have to go through this:
Use log on or log on to to refer to creating a user session on a computer or a network. Use log off or log off from to refer to ending a user session on a computer or network. Use sign in and sign out to refer to creating and ending a user session on the Internet.
Do not use log in, login, log onto, log off of, log out, logout, sign off, or sign on unless these terms appear in the user interface.
So while Microsoft stands with the AP and the American Heritage Dictionary in its hyphenless logon and logoff, it directs us completely away from both login and log in, throwing us another couple of curves. According to Microsoft’s senior editors, you log on to and log off from your computer and your company’s intranet, but you sign in to and sign out of, say, your Xbox account.
Clear as mud, right?
If you strictly adhere to either Chicago style or AP style, your options are sufficiently narrowed and relatively clear: hyphens in Chicago style, no hyphens in AP style. Whether you log in, log on, or sign in to or sign out, log off, or log out of (or from) a computer, program, or network is largely a matter of personal choice within the restrictions of your house style. Attempting to decree absolutely that one option is correct and another is incorrect would be misguided.
However, if you’re building your own convention sheet or style guide, consider this: Unhyphenated forms of the nouns are currently more popular than the hyphenated forms, and that doesn’t seem to be changing. The Chicago Manual of Style itself notes a “trend toward closed compounds.” If you’re looking toward the future, and if the choice is truly yours, the unhyphenated nouns look like where we’ll all be in the end; Merriam-Webster will catch up eventually.
And regardless of whether it’s login credentials or log-on screen or any of the various iterations, the verb forms should keep that space: You’ll never *login to a computer.