LCD definition

LCD stands for Liquid Crystal Display, which basically uses electrically-sensitive fluids to filter light (often from a back-light) with a varying current. The compounds used have both crystalline and liquid properties, hence the name. The important property however is they're light-polarising (filtering) and change based on a controlled electrical current. LCD Visual Display Units (monitors and TV's) are one of the most common display technologies in use today for computers of many kinds.

LCD's used to be only found in "black and white" and needed sufficient light from affront or from florescent or incandescent lamps behind, making them inefficient and not suitable for most in computing. By the end of the 20th century, multi-layered colour-filtering LCD screens became available and since replaced other VDU technologies due to their efficiency, compactness, weight and sharper (less blurry) images.