An optical viewfinder was always used by film cameras, and is a wonderful added option for digital cameras. I find it particularly handy when trying to photograph on a very sunny day as it enables you to see more clearly than it would with bright sunlight obscuring what you’re viewing on the back screen. On a digital camera, other than SLR’s, the optical viewfinder is completely seperate from the camera’s lens. It is used to frame the picture you intend to shoot, but has a couple of effects that the keen photographer needs to be aware of. One is that as a result of the physical seperation between the viewfinder lens and the camera lens, the image does not exactly match up. The technical name for it is “parallax phenomenon”. It is much more evident when taking close up shots. If you are aware of this, then you can make the adjustment to compensate for this error. The second issue to be aware of is that the optical viewfinder sees about 80% of what the camera lens sees and as a result you will often find that unwanted and unattractive content around the borders. Once again, awareness of this enables you to realize that a small amount of cropping may be necessary. This camera knowledge helps optimize your chances for really great photos. Good luck!