The bank sites I'm on tell me to logout.
Are you sure, Tom? The two banks I do online banking with both invite me to
log out, and to
log on at the start of a session.
In general, the two-word forms of these expressions appear to be used more frequently than the one-word versions, except in the case of
login/
log in.
Here are some counts from GloWbE, the 1.9 billion word corpus of Global Web-based English
log in 8446
log out 898
log on 4112
log off 458
And the one-word forms -
login 15948
logout 381
logon 1163
logoff 54
Why are the starting up terms used more often than the finishing ones? One reason is that
login, etc are often used for the details you use for signing on: "login name", "login details" or simply, "I've forgotten my login". Also we have the place where you log in, the "login screen", etc. There are no equivalent uses for
logout.
I suspect the reasoning behind the suggestions made in this topic is that we must be consistent. If
login is common, then
logon, which means exactly the same thing, must be common too, even if it is used much less often. And
logout, which is the opposite of
login, must also be common, even though it is used even more rarely. And following through on the chain of reasoning,
logoff should be common also, even though
login is used 295 times as often.
But actually, why? I can see there's a strong case for being consistent in allowing all of these as words, which we have done for several years. But whether a word is treated as common must take some account of how commonly it is actually used. On occasions I've been swayed by consistency pleas when I probably shouldn't have. I agreed to a suggestion that all the letters of the Greek alphabet be treated the same. Since some words, like
alpha, are obviously common, others like
theta and
zeta are common too now.
I'm inclined to think
logon should be common now, and possibly
logout, but I have grave doubts about
logoff. It doesn't even look like a word!
I'll leave this issue open for a while in case there are further comments from anyone.