Syphon lets Mac apps hand each other frames directly on the GPU: a generative patch publishes its output, a VJ mixer consumes it as a source, same machine, effectively zero latency. Since 2010 it has been the connective tissue of Mac visual rigs.
The pattern it enables is modular performance: generate in one tool, composite in another, output from a third, each doing what it is best at. Most serious Mac visual software speaks it.
Windows’ equivalent is Spout; between machines the job passes to NDI. Anyone building a multi-app rig learns all three names in the first week.