Dialer

A dialer (also called a spyware dialer) is a software program that connects a user's computer directly to the Internet or other online service via a modem. Some dialers are useful, but others are malicious. For example, a malicious dialer could call a 1-900 telephone number, an adult phone line, an international toll number, or another destinations that a user did not intend to call, resulting in large charges on the user's telephone bill.