In our designs we use 1200px grid system as a base for content layout design. There are many reasons 1200px is a good solution to content layout. You can find more at http://1200px.com/. With the advent of responsive design it’s even more important a grid system is used for design.
1200px grid system has been composed of 12 columns by 70px wide and 11 gaps by 30px wide. Real useful area width is 1170px, and that is what we can use for real content. Additional 30px from 1200px grid name are paddings – 15px on the left hand side of first column, and on the right hand side of the last column.
Some examples of our designs using 1200px grid are: