Resolution is a parameter that measures the amount of data contained in a bitmap image. It is usually expressed as pixels per inch (PPI) and dots per inch (DPI). (1) Image Resolution The number of pixels per unit length in an image is referred to as image resolution, measured in pixels per inch (PPI) or pixels per centimeter. For two images of the same physical size, a high-resolution image contains more pixels than a low-resolution one. Image dimensions, image resolution, and image file size are closely related. Larger image dimensions and higher image resolution result in a larger image file size. Adjusting the image size and resolution can change the file size of the image. (2) Screen Resolution Screen resolution is the number of dots displayed per unit length on a monitor (DPI). It depends on the physical size of the display and its pixel settings. When the image resolution is higher than the monitor resolution, the image displayed on the screen appears larger than its actual size.