Broadband is an electronics engineering term often used to refer to high speed Internet services. These are Internet services that are faster than phone-based dial-up, and are always connected. DSL is one of the two leading technologies used to provide broadband internet. The other is cable; satellite, fiber optic and others are less common.
DSL stands for Digital Subscriber Line. It uses existing telephone wiring, but does not interfere with telephone service. When added to a regular phone line, special filters are required for phones, fax machines, alarms and any other equipment on the line. The speeds and costs of DSL are generally comparable with cable. Choosing between DSL and cable may come down to the availability of each service. Due to technical limitations of DSL, it is not available on all phone lines, and there may be additional costs if a phone line is not already being used for phone service. Residential DSL, like most broadband Internet, is usually asymmetrical (ADSL), which simply means that downloading is faster than uploading.