They're related. Field of view is described in degrees, and refers to how far off the centerline of the lens something can be seen. If you look down the center of a paper towel roll, the field of view is very narrow. By comparison, the SJ7's lens can cover 170° or a little more than total field of view for most people.
We don't see the fisheye effect because the retina is round. The light rays hitting the retina are always perpendicular (at right angles) to the retina; there's no distortion.
With a camera, only the light rays coming down the centerline of the lens hit the camera's "retina", the sensor, perpendicularly. The further out from the center, the greater then angle and that ultimately shows up in the rounded "fisheye" look. One good example is to stand almost in a door frame, near the edge of the field of view. The straight door frame will look almost circular, although your eye sees the sides and top as straight lines.
Distortion correction tries to undo the problem, but it's still not going to be exactly as we see the same scene with our eyes.
