Creative use of focal length
Focal length indicates whether a lens is wide angle, telephoto or anywhere in between.
Generally speaking, using wide angle is ideal for shooting scenes such as land and city landscapes, group photos and room interiors. For portraits, a mid-range focal length is a good choice. Long telephoto lengths are ideal for photographing wildlife and distant subjects.
Focal length as a creative tool
Focal length selection can be used creatively when composing a shot, beyond simply getting more or less of a scene into the frame. The focal length you choose plays an important role in composition and the "feel" of an image.
Wide angle effectively exaggerates distance and shrinks distant subjects. Telephoto compresses distance without shrinking distant subjects.
For example, if you were to take two shots of a landscape with an object in the foreground such as tree, rock or flower, etc. and an object such as a mountain in the background using a wide angle and then a telephoto, they would look very different though framed in the LCD (or viewfinder) in a similar way.
Selecting a focal length to achieve the effect you want can be just as important as selecting the right aperture and shutter speed. Focal length can also be used to vary the emphasis on an object/subject.
