A tablet PC is a one-piece mobile computer. It is generally smaller than a laptop, but larger than a smartphone or personal digital assistant (PDA). This makes the tablet very portable without losing too much of the size of a personal or mobile computer. Tablets are controlled by a touch screen, with a limited amount of physical buttons. The touch screen often brings up a virtual keyboard which can be used with either one's fingers or a stylus. Tablets also have the ability to connect to physical keyboards and peripherals. Tablets generally can do almost all the same things a personal computer can do such as connecting to wireless Ethernet, but they also have the advantage of using wireless broadband connections to gain internet access wherever broadband wireless connections are offered. Performance, size, and battery life are critical aspects of next-generation tablets.