Input-Output possibilities
PD allows you to play with a lot of information, you can mix it and create things with:
-communication with other pd's over tcp/udp [netsend/netreceive]
-shell in/out [pdsend/pdreceive]
-Open Sound Control, Flosc
-audio stream in/out
-video stream in/out
-serial/parallel port in/out
-midi
-hid devices (keyboard, mouse, joystick, ...)
-multichannel audio (alsa/jack, asio)
-browser plugin iARS (developed upstairs)