"For the benefit of the complete beginner: Inkscape is a vector
drawing program. That means that it creates graphics which can be
scaled without adverse effect on quality. These won't be photos or
other such graphic work, but more usually they are found in logos,
clipart and other places where the image may be scaled up or down.
If you enlarge a small photo or bitmap image you get pixelisation
and "jaggies". Do that with a vector graphic and you'll find the
linework is as smooth as the smaller version. Inkscape uses the
open standard Scalable Vector Graphic format (svg), but it will
import popular vector formats like Adobe Illustrator and wmf."