What is raster artwork?
Raster refers to an image composed of pixels on a grid. Raster graphics are measured in Pixels Per Inch, or ppi.
Raster images have a fixed amount of colour and resolution information.
If you scale up a raster image (e.g. 100% to 200%, the size of the pixels increase and the image quality decreases. Alternatively, as you scale down raster images (e.g. 100% to 50%), the size of the pixels decrease and the image quality increases. Common raster file type include JPG, PNG, TIFF, and GIF. Recommended resolution for digital printing - files built to 100% scale, as outlined in this .