Compatibility

The Strengths of HTML

HTML was originally designed in a world of variety in computer systems, software programs, manufacturers, and generations of computers. It was created knowing that a single language would need to be compatible with many types of computer systems. Some would have small screens, while others would have large screens. Some could display graphics while others could not. Some systems would have many fonts installed while others would have very few fonts. Many different web browsers (not including Internet Explorer) were designed to interpret the HTML code into a visible, user-friendly format.

One of the most important characteristics of a well-written web page is compatibility. This means that it must be viewable by users on many different types of systems and with different needs.

Screen Sizes

Since users have many different screen sizes, you as a web designer cannot assume that what looks good on your computer will also look good on another computer. Although it is not easy, you must build your web pages in such a way that they look good on small screens and on big screens.

One way to test this aspect is to try reducing your browser window to a smaller size. Your web page should be still visible on the smallest screen size a user might have. At the same time, it should be able to handle a large screen size.

Fonts

As we have already discussed, you should not use a font in your web page that other users may not have on their systems. If you do, you should always specify alternate font choices that others are sure to have. Failure to do this might produce a web page that looks very different from how you originally designed it.

Accessibility

Some special needs of certain users must always be considered. Users may have physical disabilities that prevent them from browsing a web page easily. Web pages must be designed to be usable by people who cannot use the mouse, have vision problems, and even for blind users.

How is this done? Most browsers allow a user to press the tab key to cycle through all of the links on a page and press Enter to “click” on a link. In addition, because fonts are defined relative to a standard font, the words can be made bigger for people who have poor vision. Finally, web users who are blind may have a computer software program that “reads” the web page out loud to them. For this reason, you should always specify the ALT property for images, allowing even a blind user to know what the picture is.

Class Exercise: To understand some of what vision-impaired web surfers must deal with, try out the simulations at WebAIM.