Everybody is using those phrases but I've never asked that question. What is really behind the words
As an extension I'm also asking:
Are those phrases still valid nowadays when you'd write "I'm online on ..."? Because you aren't directly connected. (I know that it could be, by just using a direct connection using only one cable as example, but by ignoring that the connection isn't direct - right?)
My thoughts about them:
Offline is an abbreviation for the usage of saying "I'm (
not) connected to the ethernet!" or "You could (
not) phone me now, because I'm (
not) in the line!".
The second example is referring to the past, where only one was able to phone someone at the time.
Please also note that I've read the wiki information and I've also looked them up inside dictionaries, so it won't be helpful seeing them as answer/comment...