As you've surely noticed upon viewing any of your documents, SVG renders all objects with anti-aliasing as a default. If you are not familiar with the concept of aliasing and anti-aliasing, a brief overview is in order.
Aliasing refers to the display quality of objects where no edges are smoothed or softened. This often leads to a look that appears bit-mapped or hard-edged. Although this was the default display of computer monitors for years, the past decade has seen a push for the softening of onscreen edges to more accurately mimic the appearance of offscreen edges. As arcs and curves must be rendered onscreen as a series of pixels, a method called anti-aliasing was created to soften the harsh ragged edges of curve rendering.