In Photoshop, the image's color patterns include RGB mode, CMYK mode, GrayScale mode, and other color patterns. What patterns are used to design image patterns, depending on the end use of the designed image. If the designed image is to be printed or printed, it is better to use the CMYK color pattern, so that the colors seen on the screen are close to the output, printed colors or printed colors. If the image is gray, it is better to use the GrayScale pattern, because even though the image is expressed in CMYK color mode, it still looks neutral gray, but its disk space is much larger. In addition to gray image printing, as represented by CMYK model, a film and printing 4 edition, the cost is not that big, but also may cause printing gray balance control is not good when the partial color, when the color printing ink amount is too large, will produce color gray image. If the design is for electronic media display (such as web pages, computer projection, video, etc.), the image color pattern is best used in RGB mode, because the RGB pattern is more colorful and richer, and the picture is better. And there are only 3 channels in the image, less data, and less disk space.