Why the parellel layout
Compared with the nested design, the parelle design removes 3 pair of extra wrapper divs in 4 columns layout, including the relevant CSS codes.
What's the difference
This design uses left rather than margin to seperate the columns, that's why the position is relative. It works well for both fixed and liquid layouts
liquid or fixed?
To use liquid layout, just set the unit to % . For fixed column, set it to px or em. Be careful to use em coz em layout is
relevant to the font-size defined in body tag.