Resolution/colour depth
The term resolution describes the number of details in an image. In the case of raster image files the resolution is defined by the number of pixel. The number of horizontal pixels and the number of vertical pixels are usually specified. The higher the resolution, the more details can be stored in an image.
Each pixel (in the case of vector graphics, each color-defined vector) has a specific color and brightness value. These color and brightness values contain a fixed number of possible gradations, as well as the actual color and brightness information. The number of possible gradations are specified in bits. For example, an RGB image with 8 bits per color channel consists of a maximum of 16.8 million colors (2⁸*3). The greater the color depth, the more colors and brightness differences can be stored.
Which color is represented by the respective color value is determined by the defined color space (RGB, CMYK). ICC profiles specify the color space of an input or viewing/printing device, making it easier to reproduce an image file correctly.