Counting as logged in

If I open up my internet browser and visit the forum then go somewhere else on the internet then leave this browser open all day am I counted as being "online now" in the forum?

i think you are, unless you completely log out.

No - once you leave the site you are not counted as being online.
The staying logged in feature is more for your browser - a cookie. that logs in for you each time you log in.

So when you see "online now" it is the total number of people with the forum open in a web page.

thanks master daf