Proper, multibrowser way to query width/height

[SethCall]

Actually, the title isn't all i am curious about.

How does one query any style attribute of an object using JavaScript?

How do i query width? height? visibility?

I try things you would expect,
such as
var query = obj.style.height;

but that doesn't work, or only does sometimes, or only in some browsers, and so on.

Any help would make me do a little dance ;)

[Brett_Tabke]

Try starting with something most of us do daily: screen resolution from java script [google.com].