SLR: Single Lens Reflex cameras.
It has a mirror that allows you to look through the camera lens uptil the actual moment of shooting. As you are looking through the lens, what you see is what you get. And, no, cameras with electronic viewfinders don't classify as SLR as they don't have the mirror mechanism. And electronic viewfinder nowadays still cannot equal the viewfinder of a true SLR, no matter how crappy.
Hee~! I was just thinking about the classic camera that have fixed lens, and was using the "new" SLR technology, when you mention this fixed lens SLR thingie. Spot on blurblock! :thumbsup:
Think a lot of people have the perception that SLR refer to those camera that have the capability of changing the lens, and not realising that SLR only refer to the technology in which the image is reflected directly to the viewfinder. There are indeed SLR camera that have don't have the capability of changing lens, and there are also non-SLR cameras that have could conversely use different lenses. Confused?
TLR = Twin Lens Reflex, instead of using Single Lens Reflex like SLR, it uses two lenses instead of one. It does not have lenses to change and the lenses on the body are fixed. The concept is used in Entry Level Medium Format Camera, such as Yashica TLR or Seagull TLR. They are known as 120/220 format instead of the 35mm format as we commonly know. However, I am not a Medium format user, thus I can't really comment about that.
Prosumer = Professional Consumer (or something like that, terms created by camera creator to differenciate between Consumer and slightly above consumer but below professional bodies).
FZ10 is just one of the Prosumer camera. Gray area there. Then there is of course the Point and Shoot Idiot Proof camera which I can never get the hang of.