Command buttons

Command buttons are used to trigger an event. Two common types of HTML command buttons are Submit and Reset. The Submit button is used to submit the contents of a form to a server-side program; the Reset button is used to clear a form. A third type of command button, called a Push button, can be scripted to execute a variety of other events (e.g. Print, Delete, Search). (Using scripted Web widgets will be discussed more thoroughly in the next article.)

Usability problems

Using reset buttons

A reset button clears all values that a user has entered on a form. According to renowned usability expert Jakob Nielsen, reset buttons offer users little to no benefit and should not be used at all. In his Alertbox column (see Resources), Nielsen points out that users have another choice: To edit the erroneous fields and replace the old text with new text. In most cases, Nielsen believes this option is sufficient. He adds that not including a reset button in the interface also eliminates the risk that users might accidentally erase an entire form.

Inconsistent behavior

It is tempting to use command buttons in a variety of ways. Too many button behaviors, however, can be confusing. On the My Yahoo site, for instance, command buttons are used in the traditional sense and for navigation (see Figure 16). Even though a label like "Change Colors" sounds like a command, clicking on this button actually takes users to a new page. On the Web, standard conventions for navigation are text links, image links, and tabs. On the other hand, the "hide buttons" text link is a command and should be displayed as a command button.

Figure 16. My Yahoo navigation command buttons

Inconsistent placement

If your Web site contains a variety of forms, wizards, or dialogs, do not make users relearn your layout every time they see a new screen. Place command buttons in the same general location. Submit buttons should be at the bottom of the screen. Reset buttons (if used at all) are usually close to the submit button. You may want to consider finding a less dangerous place for the reset button to prevent users from accidentally clearing a form.