If it wasn't, it would look even more jagged. When scanning graphics into applications that deal with bitmap data only, make sure that you scan the image in at the exact size that you need. This will prevent you from having to resize the image and compromise the quality. The other type of graphic is called a vector graphic. Vector graphics do not use pixels and are based on mathematical formulas that represent curves and lines.
Vector graphics are very smooth looking and can easily be resized without loss of image quality.
This is not a math tutorial so we will try not to go too in depth, however, the following example may clear up what makes vector graphics so sharp and scalable. It already is. An EPS essentially places a PostScript wrapper around your image and preserves all of the image data. In the case of a vector image, the mathematical equations that represent your vector image will remain and not be converted when brought into the application.