Field of view (FOV) is the width of the view you see through your binoculars, measured in feet at 1000 yards, or meters at 1000 meters. It can also be expressed at angle of field of view (e.g. 7 degrees). Usually the FOV is impressed somewhere on the binoculars along with magnification and aperture. FOV of a binocular is determined by power and eyepiece design. Generally speaking, the greater the magnification, the narrower the field of view. If you intend using your binoculars for moving objects like birds or a cheetah in hot pursuit, you should not go for more magnification than 8x.
Binoculars with exceptional field of view are discussed in “Best wide angle binoculars“.
If you’re looking for affordable binoculars with above average field of view like for children, I suggest you read my article on Binoculars for kids II.