The main difference between vector and raster graphics is in what they’re composed of. Vector graphics are made of points, creating a smooth, crisp design (best used for print when the file contains text). A raster graphic is an array of pixels of various colors, which together form an image (best used digitally or for photographs or designs that do not contain text).
To ensure your text-based graphics or design are saved to properly maintain their vector elements, you’ll want to ensure that all transparencies are flattened, overprint is turned off and all fonts are outlined or converted to shape.
For best results, we recommend using the following preset to preflight your designs: Adobe PDF/X-1a:2001.