I would like to purchase a Nikkor telephoto lense but what does all this mean?

AF-S Nikkor 300mm f/4D IF-ED?
I looked up the specs on Nikon's website but i have no idea what they all mean or how they work… Is anyone familiar with they mean?

Added (1). oh, and I have a 70-300 mm telephoto lens but its an older version, the kind that extends manually. I picked this one because its compatable with both my D50 and my N75.