This is the first column, which is enclosed in the div called "column1" and has a float left rule. Since it is the first in the list, it orients to the far left. Generally, the far left column is used for navigation bars or decoration with images.
This is the second column, which is enclosed in the div called "column2" and also has a float left rule. Since it is the second left-floated div, it floats next to (right of) the first div. Generally, this middle column would have most of the content.
This third column is "column3", is the third left-floated div and floats next to (right of) the second and shows how variable sized content in different columns will display.
