The border attribute allows you to specify whether a region should have a one-pixel wide or size border around the perimeter of the region's viewport. If the region has no other frame attributes, and a line border is desired, you can also specify what color it should be drawn in.

Note that dialog regions do not allow color borders.

If a line border is desired and other frame attributes are being specified for the region, the color of the line will be whatever color has been set in the operating system for the window border color. The user can set this color from within the Control Panel.

If a size border is desired, it will also be the color set in the Control Panel. The user can set its width from within the operating system Control Panel. A size border on the region allows the user to resize the region. The operating system handles the actual resizing of the region. This means that you do not have to write a response for the object in order to allow the user to resize it.