Okay, I have a raspberry pi, I use the pins to control LEDS and etc, but I have been thinking recently about using the pulses I can create from the raspberry pi, to control multiple things over a simple USB lead, is it possible to take pulses from a input and transfer them into something a computer can understand? Thank you, sorry if this question is vague, not good at explaining things..
Absolutely. This is actually similar to how infrared communication such as TV remote controls work! Only difference is you want to have actual copper rather than infrared light as your transmission medium
Check out Pulse Modulation methods to get an idea of the foundation. The only application I can think of using this is IR communication which sparkfun has an amazing explanation on, but I'm sure there are other applications using this method you explain
As Chris Stratton noted, you would typically use a low level serial communication protocol for chip to chip communications. Typically SPI or UART if you need a lot of bandwidth, otherwise you could just use I2C. The Raspberry Pi has hardware engines for these protocols as well.