As to the difference between margin and padding, margin is the space outside the element, and padding that inside it. If they inherited, then if the BODY had a 2-inch left margin, P would start four inches from the left of the page, etc. The containing block All element have a containing block. Elements are usually aligned with the edge of their containing block. This defines the containing block for descendant elements.
All browsers have some problems with box properties.
Beyond this, you may have problems, the most notable of which I detail below. IE 3.00 interprets all margins as relative to the left of the page rather than the left of the element. The box shorthand property allow you to specify the box style for all four sides at once. Margin Clearly each element can have four margins - left, right, bottom and top. The margin can be specified in any length, a percentage, or using the auto keyword.