In photo magazines and among retailers you often read about the 'The ultimate travel lens'. What they mean is these superzoom lenses. A superzoom is a lens that often has a focal range of 18-200 mm, for example, which covers a wide variety of uses. It combines a wide angle lens, with a normal lens and a telephoto lens. By having these specifications you can use the lens for pretty much everything you need to photograph. The lens becomes ideal for those who do not want to drag along several lenses or for those who want to avoid the risk of getting dirt in the camera when changing lenses too often. In order to get such a wide focal range the lens manufacturer might need to compromise a bit on the optical parts, and that can sometime result in suffering image quality and maximum aperture value (lens brightness capabilities) but at the same time you get the maximum flexibility and convenience available to the market.