Well, on older (non-auto-sensing) devices, it actually does make a difference (the crossover cable crosses pins so that the transmit [tx] wires of device A connect to the recieve [rx] wires of device B and the same for B to A). However, most modern devices can detect what type of cable is used, whether it's a crossover or straight cable, and automatically switch its transmit and recieve lines to match the cable. But yes, straight and crossover are both types of cat-5e or cat-6 cable, which is "Ethernet cable" (main usage is for Ethernet protocol/hardware networks).