Internet Explorer 6.0 sp2 information bar on limited account

What's the difference between running the internet explorer 6.0 sp2 on
Limited Account and Administrator Account? because sometime when use IE 6.0
sp2 on administrator to browse the internet i see information bar pop-up that
has a blue shield/question mark i think it's a security questions icon with
message this site might require the following ActiveX control: click here to
install on a the website but when i use IE 6.0 sp2 on limited Account i
don't see the information bar at all that has a blue shield/question mark
icon. can some one explain please? or direct me to a website which explain
the difference when running IE 6.0 sp2 on limited and administrator.