Raster graphics are digital images created or captured (for example, by scanning in a photo or taken from a digital camera device).
A raster file is usually larger than a vector graphics image file. A raster file is usually cannot be edited, changed or modified although there are software tools that can convert a raster file into a vector file for for refinement and changes. Examples of raster image file types are: BMP, TIFF, GIF, and JPEG files.
Above logo (Quiksilver) is an example of poor resolution logo file with pixilated form. This type of logo cannot be used for printing or engrave as the machine cannot recognise the file and/ or even it can be exposed thru a film making process, the printed result will be unlikely to be accepted.