A thin, highly concentrated beam of light which is used in audio to read digital media such as CDs, DVDs and laserdiscs. Lasers are very fine enabling a large amount of data to be held on a small surface area. he term laser is actually an acronym for Light Amplification by Stimulated Emission of Radiation. The laser operates by shining on a digital medium (such as a CD) and reflecting off the surface of the disc. The reflected light is read as having hit a land (baseline area) or a pit (small trench in the land). The areas where lands and pits shift (pit ends or land ends) represent ones and zeroes, the language of digital equipment. The laser light is determined to have hit the land or pit on a disc and a stream of one and zeroes is created from reading the reflected light thus creating a complete digital signal.