The Copper Wire Internet

DSL, which stands for Digital Subscriber Line, operates on the same copper wires that phone companies use for traditional telephone service—so-called landlines—albeit on a higher frequency range that doesn’t necessitate tying up a phone line the way dial-up service does. (Kids, ask your parents.) Phone lines were built to transmit voice, which doesn’t require a whole lot of data, so they tend to be s‑l‑o‑w.