Internet appliance, also called net appliance or Web appliance, is an inexpensive computer designed primarily to provide a connection to the Internet. Its capabilities are more limited than those of a personal computer. But the device generally provides a user with the same Internet capabilities that a personal computer does, such as the ability to compose e-mail messages, perform searches on the World Wide Web, and perform business transactions. Some Internet appliances also include features that are not associated with the Internet, such as the ability to control other devices or systems in the home or to play compact discs and DVD's. An Internet appliance links to the Internet through a telephone line or through a high-speed communication network, such as a cable television system or a DSL (digital subscriber line) network. A net appliance generally includes a small monitor, memory chips to hold data, and a keyboard. It does not have a hard drive, so it cannot store files. However, a user can expand the appliance's capabilities by attaching an external hard drive, a printer, or other components.