Bored with math calculations of golden ratio? Thinking of quitting? Just divide it into three, and you’re ready to design. We don’t need to be always exact on every pixel unless when we start to code. Using rule of thirds in creating a draft for your first layout is a good practice.
This idea is based from the Golden Ratio. The smaller part is somewhat 1/3 of the whole rectangle, and the longer part is almost 2/3 of the whole. The rule of thirds is widely used in photography. This is a guide to make images and graphics more appealing to the eye. Some digital cameras have this feature to capture images using this idea. You can see more examples in http://www.photo96.com/blog/?p=371
You can use this guideline when cropping images and positioning objects on your designs. It is an advantage if you have some basic knowledge in photography when you want to become a web designer. Rule of Thirds is the foundation of creating a grid.