Dialers are malicious programs or viruses that can cause a computer to dial a telephone number which is usually premium rate in order for the writer of the dialler program to gain money for the phone call costs. These programs need a dialup modem in order to operate. With the fact that the majority of people now use broadband or adsl for internet access these are not very common any more. They can however still affect computers using modems for things such as fax transmissions etc. There are also a number of new dialer viruses emerging that may affect the latest versions of some mobile telephones.