The smallest complete sample of an image.
In web design pixels are often used as a measure of image size or screen resolution (e.g. banner advertisements are 468 pixels wide) or an image resolution is 300 pixels per inch (also dots per inch, dpi). In computer programming, an image composed of pixels is known as a bitmap image or a raster image. The word raster originates from analogue television technology. Bitmap images are used to encode digital video and to produce some types of computer-generated art.