Handheld computers also personal digital assistants (PDAs), are battery powered computer small enough to carry almost anywhere. All thought not as powerful as desktop or laptop, handheld all useful for scheduling appointments, storing addresses and phone numbers, and playing games. Some have more advance capabilities, such as making telephone calls or acessing the internet. Instead of keyboard, handheld have touch screen that you use with your finger or a stylus (a pen-shaped pointing tool.)