Extreme Long Shot - This normally shows an EXTERIOR, e.g the outside of a building, or a landscape, and is often used to show scenes of thrilling action such as a war film or disaster movie.
There will be very little detail visible in the shot, to give a general impression rather than specific information.
Long Shot - This category includes the FULL SHOT showing the entire human body, with the head near the top of the frame and the feet near the bottom. While the focus is on characters, plenty of background detail still emerges: we can tell the coffins on the right are in a Western-style setting, for instance.
Medium Shot - Contains a figure from the knees/waist up and is normally used for dialogue scenes, or to show some detail of action. Variations on this include the TWO SHOT (containing two figures from the waist up) and the THREE SHOT (contains 3 figures...). NB. Any more than three figures and the shot tends to become a long shot. Background detail is minimal, probably because location has been established earlier in the scene - the audience already know where they are and now want to focus on dialogue and character interation.