The FoV, Field of View, refers to the area visible from an observation point and is expressed in degrees.

In cameras, binoculars or telescopes, it represents the angle of observation expressed in degrees, the greater the FoV, the more we can visualize a large area. The higher the optical magnification, the lower the FoV. Consequently, with a large FoV (usually produced by wide-angle devices), the magnification will be lower and we will look at the objects as if they were more distant, compared to reality.