One very common practice with HTML, is to use HTML tables to format the layout of an HTML page.
A part of this page is formatted with two columns. As you can see on this page, there is a left column and a right column.
This text is displayed in the left column.
An HTML is used to divide a part of this Web page into two columns.
The trick is to use a table without borders, and maybe a little extra cell-padding.
No matter how much text you add to this page, it will stay inside its column borders.