Most users connect to the Internet, using a modem (modulator/demodulator-an electronic device that converts signals to enable a computer to be connected to an ordinary telephone line), through a server and router owned by an ISP (Internet service provider). Often they have to pay the ISP a fee to make a connection, usually depending on advertising on the webpages to pay for the service or charging premium rate telephone line charges for helplines that provide help and support services.With free ISPs, the user only pays for the telephone call connection which is usually a local connection.