A dialer is a computer program which describes usually a program promoted as a "Free Downloader" or "Browser Plugin" for payments of service through providing pornographic services. However a dialer can also describe a telephone dialer program which will let the user make ordinary telephone calls through the computer, speaking through a microphone.

If they are not careful, innocuous users who glanced through the fine print may be charged on their phone bill up to $4.00 or more per minute for use of these malicious dialer applications, depending on the service provider.

Internet Explorer users must be aware of the security warning windows which displays the properties of an browser plugin or active X (Which enables install on demand or install and run from the browser), since such programs are usually disguised as sex dialers.