Pan and scan is a method of adjusting widescreen film images so that they can be shown in fullscreen proportions of a standard definition 4:3 aspect ratio television screen, often cropping off the sides of the original widescreen image to focus on the composition's most important aspects.
Some film directors and enthusiasts disapprove of the pan and scan cropping because it can remove up to 45% of the original image on 2.35:1 films or up to 53% on earlier 2.55:1 presentation, changing the director or cinematographer's original vision and intentions. The most extreme examples remove up to 75% of the original picture on such aspect ratios like 2.76:1 in epics such as Ben-Hur and It's a Mad, Mad, Mad, Mad World. Lawrence of Arabia is an exception to the 75% rule because its aspect ratio is 2.20:1.
The vertical equivalent is known as "tilt and scan" or "reverse pan and scan". The method was most common in the days of VHS, before widescreen home media such as Laserdisc, DVD, and Blu-ray.
The center cut is similar to the difference as the name suggests that it is simply a direct cut of the material from the center of the image with no horizontal panning or vertical tilting involved. This method doesn't require the permission or availability of the filmmaker or director to identify the most important part of each frame. Most video displays have three options for 16:9 widescreen frame formatting, which are either center cut, letterbox or full frame. The first two options are reliant on the video stream's aspect ratio flag being set correctly.