Attached Link: http://www.nikonians.org/html/resources/guides/uv_haze_skylight/uv_haze_skylight_filters1.htm

Sheila maybe this will help in understanding the difference.... which is fairly minimal. UV's and skylight filters are generally lumped together because they all cut out UV light, albeit with very subtle differences. If your looking to eliminate blue and haze then a polarizer would be a better choice imho, or if you want to warm up a bright scene a warming filter.... I just wanted to share this passage from one of my favorite photo books "John Shaw's Nature Photography Field Guide", because I thought it followed along with this discussion in a certain way.... I'm not trying to change anyone's mind about using them, indeed my only concern is my own photography, but it does follow along my own thoughts on this, and maybe gives a better explanation into my own opinions on the matter as well. John Shaw says: "I see many photographers who always leave a filter--usually a skylight or UV-- mounted on their lenses as "protection". I've never understood this concept. From what are they protecting the lens? Dirt and fingerprints? If so, then you must remove that dirty filter before every shot. Better always to use a lens capt to keep the front element clean. Salt spray? Great, use a filter in this situation. But if you're not working in blowing salt spray, then your reason for the filter has disappeared. Use all filters only when appropriate. If you can't articulate exactly why you're using a filter, if it's not a fully conscious decision on your part, then I believe the filter shouldn't be on your lens. If you still want to use a UV filter as protection then at least be aware that the added thickness that comes along with adding another filter to the lens, such as a poloarizer, might create vignetting problems. And mounting any filter on a zoom lens is an invitation to flare and ghost images unless you consistenly use a lens hood also. Zooms are optically complex, with 10 or more elements inside to bounce light around. Stick a flat filter on the end of the lens, directly in the sunlight, and you just create more potential problems. That's not to say I use no filters at all. Indeed there are two filters that I urge you to purchase. These are an 81A warming filter and a polarizer......" He then goes on to recommend that the they be glass and not acrylic resin versions.

I am, therefore I create.......
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