(Also spelled "ReWire") A protocol developed by Propellorheads and Steinberg that allows for independently running applications on a computer, such as sequencers and soft synths, to interoperate. ("Independently running" in this context means that one is not running as a plug-in within the other.)
ReWire provides for applications to pass audio, MIDI, and control data, with time synchronization. It generally divides applications into applications that produce audio, and applications that produce MIDI and accept audio to be recorded and processed. However, connections can be more ad hoc depending on how the software applications support the protocol.