How can I force my footer to stick to the bottom of any page in CSS?

Question

This is my code:

#footer {
   font-size: 10px;
   position:absolute;
   bottom:0;
   background:#ffffff;
}

I\'ve no idea what is wrong with

Answer 1

This is what I did and it caused my footer to stay at the bottom.

.footer2{
background-color:#606060 ;
color: #ffffff;
height: 30px;
bottom:0px;
position:fixed;
width:100%;
}