Are these Autofocus lenses?

[Markw]

Will these lenses AF with the D40? Im guessing thats what the "AF" means, but just to make sure. Also, what does the "DX", and "ED" mean?

Nikon 18-55mm f/3.5-5.6G II AF-S DX
Nikon AF-S 55-200mm f/4-5.6G ED DX Zoom Lens

Mark

 

[Markw]

Also, since these only have one ring around the lens to make the lens move in and out, will it always focus depending on how far you are zoomed in/out? I mean will it still focus correctly without a MF ring?

Mark

 

[reg]

AF-s will work with a D40. Those are both AF-s.

And both of them have a MF ring.