The first screensavers were developed to minimize screen “burn in” on CRT (cathode ray tube) computer monitors similar to television sets. A general slow degradation of the phosphor compound’s capacity to illuminate over time was known but the problem was the accelerated local degradation or “burn in” caused by a static image displayed over a prolonged period of time. This loss of the illumination capacity of the phosphor compound prematurely was the big concern. Then the idea came about for images that moved around on a black background. Amusing images would move...
