The object in motion, indicated by the heavy circle, is undergoing motion with no acceleration. This means that the velocity of the object is constant. In more than one dimension,both the speed and the direction of the velocit (and any other vector) must be specifed. The short line coming diagonally off of the top of the object represents the velocity of the object, which is constant in size and direction. The velocity vector may also be specifed by its components, in this case represented by the light horizontal and vertical lines coming off of the object. These represent the independent horizontal and vertical motion of the object.