Artwork (meaning your logo or any graphical element that gets imprinted on the promo product), comes in two general file types: raster and vector. Raster graphics are a compilation of individual pixels of various colors while vector files define graphics with mathematical algorithms. Vector graphics allow for better scaling and modification without loss of image resolution, as such, it is the preferred file format of most promotional product vendors. JPEG and GIF are examples of raster files, while EPS is a type of vector. In addition, it is good for you to know that high resolution images offer the better results. 300 dpi (dots per inch) is the industry standard for vector files. If the promotional product company supports raster files, 600 x 600dpi is the ideal size for submission. Your artwork may require special imprinting methods such as traps, chokes and bleeds. If this is the case, find a company who can offer you support in this area.