The Nikon D 40 is an all new affordable, compact, point - and -shoot Digital SLR from Nikon, it follows on from the D 40 but at a significantly lower price .
Perhaps the biggest negative on the D 40 is that it doesn’t have an internal focus drive motor and hence no mechanical focus drive pin Insert and it only has CPU contacts Which means it can only auto Focus with AF-s and AF-I Lenses . indeed our standard lens the Nikon 50 mm F 1, 8 D are manual focus only on the D 40
the image below show difference between the mount on the D 40 a mechanical focus drive pin .
I do still have my D 40 must say It still works very simply and everyone can make good short . the size and performance, say the 35/1.8 D X it’s still very good my nowadays