The type of photography that you do
Fast Moving Photography
If your passion is wildlife photography, for example, then you should be looking for a tele-lens, something in the class of a 200-400mm or at least 300mm. By a 200-400mm or 300mm, the focal length of the lens is referred to. The longer the focal length of the lens the further it can ‘look’ and thereby fill the frame with a subject that is at a distance.
If you’re more intrigued by still life, for example architecture, then a wide-angle lens is better suited. In that case look for a lens which offers a focal length range such as 10-22mm. This would offer a larger ‘angle of view’ and thereby cover a bigger picture ideal for both architecture and landscape photography.