Cable Modem

A cable modem is an external device that allows your computer to connect to the Internet through a cable TV wire, instead of a telephone line (or another system).

Cable boasts faster speed than DSL Internet in theory. However, cable does not always deliver on the promise in everyday practical use.
Popularity (advantage - Both): In the U.S., cable Internet enjoys significantly greater popularity than DSL, although DSL has been closing the gap recently. Outside the U.S., DSL continues to hold the edge. Both dominate the rest of the competition with millions of subscribers to each.
Customer Satisfaction (advantage - DSL): Even if a technology is popular, customers may be unhappy with it whether due to cost, reliability or other factors. Indeed, in the U.S. cable services generally rate lower than DSL in customer surveys.
Security (advantage - Both): Cable and DSL implement different network security models. Historically, more concerns have existed with cable security, although cable providers have definitely taken steps to improve security over the past few years. It's likely both DSL and cable are "secure enough" for most people's needs.