A computer display is a marvelous thing. An unassuming dark gray surface can suddenly transform into an artist's canvas, an engineer's gauges, a writer's page or your very own window to both the real world and a huge range of artificial worlds! Because we use them daily, many of us have a lot of questions about our displays and may not even realize it. What does aspect ratio mean? What is dot pitch? How much power does a display use? What is the difference between CRT and LCD? What does refresh rate mean?