most data discman models have a small low-resolution grayscale lcd (256x200 at first, then up to 320x240 and in colour for later models), a cd drive (either mini cd or full size), and a computer that is not very powerful. early versions of the device cannot play audio cds. software is pre-recorded and mostly is encyclopedias, foreign language dictionaries and novels. software was usually made using the sony electronic book authoring system (sebas).