Using audio ports on the sound card, a PC plays sound on headphones as well as records audio from a microphone. These output and input connections serve two separate roles on a PC, but users can combine them to serve a singular purpose of recording audio. With an additional hardware component, you can change the way you use input and output ports on a PC.
Purchase a 3.5mm male-to-male audio extension cable from a local or online electronics store. Two examples of cable manufacturers are Belkin and Cables Unlimited. Both ends of the cables are both male, meaning they plug into ports.
Plug one end of the cable into the headphone port. This port is usually coloured green on a PC. This port on a stereo player or boom box is usually imprinted with the icon of "headphones."
Plug the other end of the cable into the microphone port. This port is usually coloured red on a PC. This port on a stereo player or a boom box is usually imprinted with the icon of a "microphone."
Use any program that can record sound via the microphone port, such as the free "Sound Recorder" in Windows 7.