DSL stands for Digital Subscriber Line, and is a type of technology that transmits data over a phone line.
This is very old equipment and mostly obsolete in the days of much faster Fibre to the Cabinet and full fibre broadband.
The most common type of DSL is ADSL (Asymmetric Digital Subscriber Line) typically known as standard broadband, which allows connection to the internet.
You will see ADSL broadband sold as “up to 17Mbps” speeds.
ADSL works simultaneously with a telephone line so you can access the internet and still use it for calls, unlike the previous generation of internet technology, dial-up.
But ADSL speeds are extremely limited. And the connection is ‘asymmetric’, meaning downloads are much faster than uploads. This contrasts to full fibre which is a symmetric connection, where upload speeds can match download speeds.
DSL’s days are numbered with the growing prominence of fibre broadband which allows for much greater data speeds.
However, very cheap broadband using DSL services may still appeal to basic internet users who simply want to get online for the lowest possible cost.