Graceful Degradability

A basic problem of Web page design is that there are many different kinds and versions of browsers out there. A design objective should be for your pages to "gracefully degrade," that is, remain functional even when viewed by older browsers or browsers not preferred by the page designer. As you try new features and designs, take time to try them out on a variety of browsers. Otherwise, some of your viewers may not benefit from your pages.

Example

In the following example, a page was designed using the following methods:

• Tables were used to create a blue bar at the top of the page to contain navigation links. The blue color was created by setting the background color of the table to blue.
• Style sheets were used to set the background color and to specify san-serif font for the headings and navigation links

Internet Explorer 4

• The bar at the top has a blue background
• The background of the page is white
• Headings and navigation link texts are san-serif

Netscape 3

Netscape 3 does not understand style sheets, so all the design features specified in the style sheets disappear.

• The bar at the top is still blue
• The background is gray
• Headings and navigation link texts are serif

Netscape 2

Netscape 2 does not understand either the style sheets nor the the use of the BGCOLOR attribute in a table cell.

• The bar at the top is no longer blue
• The background is gray
• Headings and navigation link texts are serif

Overall, though, the page remains usable, so the page would be considered to "gracefully degrade." When pages fail to function on some browsers, they are said to "ungracefully degrade."