The SpriteBatch class is part of the XNA Framework that:

A.
converts 3D models into 2D graphic image sources.

B.
enables a group of 2D bitmaps to be drawn.

C.
stores an animation from a series of bitmap images.

D.
creates multiple resolutions of a given sprite.

Explanation:
http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.spritebatch.aspx