Hello everyone I have a question that I've been pondering.. And it probably has a simple answer. I'm studying physics of Telecommunications at college, and we were talking about how you can't send digital square pulses over phone lines. This would require an unlimited need for bandwidth, and the square pulses would soon become rounded and all jumbled together. ( If this is wrong, please let me know. My school doesn't have the best science depart. so I always like to double check my professors) My question is this... if we can't send data like this through a phone line, which is copper. How can it work inside a computer? Isn't the data being sent from the processor to RAM or memory on copper wires as well? How can we send digital data through a USB or Serial cable but not on a phone line? whats the difference? Are these wires somehow specially made for sending binary data?