Question: According to this quirksmode article, <http://www.quirksmode.org/css/display.html> 

> 
> A block has some whitespace above and below it and tolerates no HTML
>  elements next to it, except when ordered
> 
> 
> 

Are the whitespace above or below stated in pixels or is it just 'whitespace'?.

Answer: 
The 'whitespace' is the element's margin and can be controlled via any standard CSS unit (e.g. px, em, %, etc.)
You can use the padding or margin properties of a CSS element to specify such a thing (in any CSS unit, including pixels). You many specify something like:

```
.class 
{
   padding-left: 4px;
   padding-top: 3px;
}

```

The difference between padding and margin has to do with display. The padding property puts some 'whitespace' (rather clear space, whatever is behind the element will show there) between the element and its neighbor. A margin increases the size of your element around its content; the extra space will show up as whatever background the current element has.