A DSL modem is a device that connects your home network to the internet using a Digital Subscriber Line (DSL) connection. It converts digital data from your computer into a format that can be transmitted over telephone lines, allowing for high-speed internet access without interrupting phone service. DSL modems typically have multiple ports to connect various devices, such as computers and routers. They can support different speeds depending on the quality of the phone line and the distance from the telephone exchange. This makes them a popular choice for residential and small business internet connections.