Computer programs work with image data in a number of different ways, for example programs like CorelDraw work with both Vector images (lines) and Bitmap images (pixels), CorelDraw is also the preferred program for making rubber stamps from images.
With baby shower clipart you don't need any special artistic skills for you to make your own beautiful baby shower cards. Not all websites provide baby clipart for free, but many do. If you want more detailed clipart you might opt to purchase clipart. But with so much free baby clip art available, you really don't need to purchase unless you really want a particular design.
By following a few simple guidelines you can save money by creating rubber stamp artwork that a stamp manufacturer can download without any design input; stamp manufacturers love it when artwork arrives that is 'ready' for production.