Standard Compositional Terms
Long Shot - LS
The Long Shot can cover a wide variety of shots, but at it's most basic it means the subject is some distance from the camera. A person in the shot may take up only a third of the frame or less, depending on how long the shot is. A Long Shot is often used to show an entire set or location. If this is the case, and it is used as the first shot in a scene, it is referred to as the Establishing Shot because it helps to establish the location that the scene takes place in.
Long Shots are used more often in film than on television, because the smaller size of the television screen makes it hard to see details clearly in a long shot. This doesn't mean you shouldn't use them in your videos, it just means that if you have important details on screen (an actor's expression, for example) they may get lost in a long shot.
Full Shot - FS
A Full Shot is just wide enough to completely show a person in frame, from their feet to the top of their head.
In general this is close enough for facial expressions to be seen on a television, but more subtle elements of an actor's performance may still be difficult to see.
Medium Shot - MS
A Medium Shot shows an actor from just below their waist to the top of their head.
This is a good general shot for most television work. A medium shot can vary quite a bit, depending on how many people you need on screen, etc. It is the workhorse shot for most dialogue scenes, allowing room for two or more actors to fit comfortably in the frame, but still close enough to the actors to clearly show facial expressions.
Close Shot - CS
A Close Shot shows from the sternum to the top of the head.
This is much more intimate than any of the previous shots, and is good for isolating your character from their surroundings or other characters in the scene.
Close Up - CU
The Close Up usually extends from the top of the shoulders/lower neck up to the top, or nearly the top, of the head.
Both the Close Shot and the Close Up are used frequently in video, because they very cleary focus the audience on the important details of your scene. Don't over do it with close ups, though, because they are most effective when contrasted against a series of wider shots. Your audience can also become disoriented if you use only close ups because the characters aren't grounded in their surroundings. However, if your intention is to disorient the audience, deliberately using only CU's can create a sense of claustrophobia and heightened paranoia because the audience can't see what surrounds your characters.
Extreme Close Up - ECU
The Extreme Close Up usually just shows one feature of an actors face...their eyes or mouth, for example.
An ECU can also be used to focus on other things in the scene..a character's hands, an important prop, etc. When used to focus on the face, however, an ECU can often help to convey a character's thoughts, which would be otherwise invisible to the audience. "The eye's are the window to the soul..." and all that.
A two shot simply means that you have two actors on screen at once, usually on opposite sides of the screen. This is often combined with other terms, for instance "Medium 2-shot" or "Full 2-shot". You can also use variations such as 3-shot, 4-shot, etc. if you have a larger group on screen.
Over the Shoulder shot - OTS
The Over the Shoulder shot is most often used in dialogues between two people who are facing each other. It generally involves seeing the back of one persons head and/or shoulders in the foreground right or left of the screen, while showing the second person's face on the opposite side of the screen. The camera is literally looking over one actor's shoulder.
When shooting dialogue scenes, it is common to alternate camera angles as the conversation goes back and forth between two actors. For instance, if your scene starts with the above OTS shot of the man as he speaks, you would then cut to a similar shot from the opposite angle when the woman begins to speak. The second shot is the Reverse Shot of the first, and a sequence which alternates like this is said to have a Shot/Reverse Shot pattern.
Point of View - POV
The Point of View shot is just that - it places the camera in a position which shows what one character is seeing at that moment.
This shot shows the man's POV from the dialogue scene above. In a sense, the POV places the audience in the character's position, making the audience feel more like a part of the scene.
Any of the previous shots can be "canted", meaning the camera has been rolled and/or tilted so that lines which would normally be aligned vertically or horizontally (such as the horizon, a person standing, or a building) are now diagonal within the frame. This is an unnatural effect, and is often used to emphasize extreme or unnatural action on screen. Frequently used in live action depictions of comic books (popularized by the old "Batman" television show) and horror films.
A low angle shot generally means that the camera is placed below the character's eye level, looking up towards them. This tends to make a character appear slightly taller, and is often used to convey heroism, strength, or dominance of some sort over other elements of the scene.
a high angle shot, as you may imagine, is simply the opposite of a low angle shot - the camera is placed above a character's eye level and usually looks down at the character. This often conveys weakness or inferiority in the character being looked down upon.