Brainwave entrainment is the practice of entraining one's brainwaves to a desired frequency, by means of a periodic stimulus with corresponding frequency. The stimulus can be aural as in the case of binaural or monaural beats and isochronic tones, visual as with a dreamachine, a combination of the two as with a mind machine, or even electrical or magnetic stimulation. The software intended to be used solely for brainwave entrainment comprise only a fraction of all of the software that can be used for brainwave entrainment.
References
Comparison of brainwave entrainment software Wikipedia(Text) CC BY-SA