Summary 5

There are three main behavior options for columns in a layout.

The first option is fixed-width. With this rule, layouts do not change as you change the size of the screen. The second option is fluid, which means the width of the columns change as the user changes the width of the browser. The final option is elastic, which is very similar to fluid except it also changess the content of the columns as well. This produces a zoom in and zoom out effect on elements.

Height and width of elements need to managed differently, and it's important to know the differences before you get to far along.

One of the only reasons you should ever set a height on an element is if the position is absolute. When you leave the height set to auto, you allow for it to grow and shrink in length to conform to the content with in it. In contrast, the width should always be controlled very carefully.

When wanting to achieve a three column, fluid center layout, there are two options to make it function.

The first way is to use negative margins to position the right column as the center changes size. The second option is to make the column containers behave like table cells using CSS3. The second option is the easier and more compatible option of the two.