Each script application has one timer at its disposal. The resolution of the timer depends on the platform. It is about 0.01 seconds on the hand-held device. The script application should implement the “on.timer()” function to respond to timer ticks. The timer continues to send ticks to the script application even when its window is not visible on the screen. The timer is automatically stopped when the document containing the script application is closed or if the script application is deleted.