Microscopic depression in the reflective surface of a digital optical storage medium such as a CD, DVD or laserdisc. Pits are like shallow indentations in the surface of a disc. A laser reads the pits and lands (the space between pits that represents the surface-level of the disc) generating digital data (ones and zeroes) where there are transitions from a pit to a land and vice versa. This digital data is then used to recreate analog signals that can be played over an audio system or displayed on a video screen.