How to put footer at least at the bottom of screen?

I have a simple website page. If it has a lot of contents the footer will be at the bottom just fine.
But let's say the page only has little amount of contents, then the footer will float above the bottom screen. How can I achieve that the footer will always at the bottom at the very minimum? (White-space thingy) It must works on all device resolution (phone, small/medium/large size laptop, etc).

Notes: Is it something like min-height: 100% on the html?