Using only CSS, show div on hover over

Question

I would like to show a div when someone hovers over an element, but I would like to do this in CSS and not JavaScript. Do you know how this can be ach

Answer 1

I found using opacity is better, it allows you to add css3 transitions to make a nice finished hover effect. The transitions will just be dropped by older IE browsers, so it degrades gracefully to.

#stuff {
    opacity: 0.0;
    -webkit-transition: all 500ms ease-in-out;
    -moz-transition: all 500ms ease-in-out;
    -ms-transition: all 500ms ease-in-out;
    -o-transition: all 500ms ease-in-out;
    transition: all 500ms ease-in-out;
}
#hover {
    width:80px;
    height:20px;
    background-color:green;
    margin-bottom:15px;
}
#hover:hover + #stuff {
    opacity: 1.0;
}

Hover
stuff