CDs are the most widespread form of optical recording media in use today. Originally developed as a means of recording audio data, CD technology has evolved into CD-ROMs, which record and store digital images and many other kinds of digital data. The inner face of CDs is scored with pits several microns long, which are arranged in a continuous spiral, and represent recorded data. Laser light is focused on these pits, and data is read by picking up the reflected light. DVDs work according on essentially the same principle.