What's the point of 960 Gridder? http://gridder.andreehansson.se/ Is it just useful for laying out websites? I'm not too clear on why exactly these grid frameworks are so beneficial...
Exactly! The 960 gridder really helps with website layouts utilizing CSS and divs, etc. where as some folks used to rely upon tables for the same thing.
I've used this one before and found it fairly easy to use: http://960.gs/
And finally, this one looks pretty easy to setup and use as well: http://www.1kbgrid.com/
The point of that kind of "Frameworks" is often to :
- Make things easier for developpers to set up a layout for their website (less reinventing of the wheel)
- Especially considering cross-browsers compatibility, which always make this harder than it should be
The grid system was inherited from print design layouts and follows the same concept as the photographic rule of thirds. The idea is to align content along specific boundaries to make your layout perceptively "easy" to view & understand.
960px comes out of trying to fit within the lowest common denominator (probably 1024x768) and the 12 / 16 column layouts are likely the highest practical divisors.
I don't think you'll find a specific technical answer for this as it's more a subjective aesthetic technique. Someone with better design/linguistic abilities may be able to describe it better :)