Relative font sizes permit the user to change the size of the website text as needed. Most browsers provide methods to enlarge and reduce the text size. In Microsoft Internet Explorer, from the toolbar, under the "view" drop down menu there is a "text-size" option.
Most browsers also include a shortcut for users with a scrolling mouse. By holding down the control key on the keyboard and simultaneously rolling the mouse scroll wheel up or down, the font size will contract or grow, respectively.