As we're about to learn, there are lots of CSS frameworks to choose from. Regardless of which one you end up with, this is where a lot of time-saving "magic" can start to happen for you and your design process.By using a CSS framework, you can quickly set up layout positioning for your mock-up. Let's take a quick tour of the top two CSS framework systems available.

960

960 grid is probably the most popular CSS framework out there because of the fact that 960 can be divided by a lot of numbers,giving you a great deal of flexibility for your layout.
You can find it at http://960.gs/.

Blueprint

Blueprint includes typography,form starters, and other plugins to choose from. It's based on a grid of 24 columns that are 30-pixel wide, with a 10-pixel margin, and the default is 950-pixels wide.
You can find out all about it at: http://www.blueprintcss.org/.