Contrast ratio is the difference between light and dark on a screen, expressed by a number. If you take the brightest white on a screen and the darkest black and compare the luminosity, you get the contrast ratio. For example, a 1000:1 contrast ratio means that the brightest white is 1000x brighter than the darkest black.
Resolution is the number of dots or pixels used to display an image. Higher resolutions mean that more pixels are used to create the image, resulting in a crisper, cleaner image. High resolution is important for projecting detailed charts and graphs, text, and high-definition video. The resolution is indicated by a number combination such as 1920 x 1200. This indicates that there are 1920 dots horizontally across the display by 1200 lines of dots vertically, equaling 2,304,000 total dots that make up the image seen on the screen.