A function of some DAWs that enables a particular track (or group of tracks in some cases) to be rendered. In fact, in most ways freeze (which does go by other names in some software) is just another term for render, but applies to the unique characteristics of an audio production system. The idea is to be able to reduce the strain on the host computer by changing real-time processes in audio files written to disk. For example, let’s say you have a soft synth track being processed by a series of plug-ins. You could freeze the track, which would basically record the whole setup, including the results of the various plug-ins to disk. Now each time you play the part back, your computer is able to easily read a single audio file from disk rather than having to do all the synthesis and processing in real-time. If you change some parameter or make an edit, the track becomes “un-frozen” or unrendered again so it’s back to being a live track – and you must freeze it again to rewrite an updated audio file.