Explaination of shot size term

VLS/WS = Very Long Shot / Wide Shot
Wide Shot is often abbreviated to WS and this term appears in a script, storyboard or shotlist to describe the size of the shot. It can relate to a person, a room interior, a landscape, a building exterior or just about any other subject you're shooting.

LS = Long Shot
In photography, film and video, a long shot (sometimes referred to as a full shot or a wide shot) typically shows the entire object or human figure and is usually intended to place it in some relation to its surroundings.

http://pfl.org/mediafiles/girl-at-the-beachby-carstenfonsdalof-flickrcom.jpg

MLS = Medium Long Shot

Framing such than an object four or five feet high would fill most of the screen vertically. Also called plain américain, given its recurrence in the Western genre, where it was important to keep a cowboy's weapon in the image.

http://classes.yale.edu/film-analysis/htmfiles/cinematography.htm

MS = Mid Shot

In some standard texts and professional references, a full-length view of a human subject is called a medium shot

http://www.eyesavingsplus.com/Images/midGirl.jpg

MCU = Medium Close Up
Half-way between a mid shot and a close-up. Usually covers the subject's head and shoulders.

http://cm1.theinsider.com/media/0/64/33/224085.0.0.0x0.432x636.jpeg

CU = Close Up
In film, television, still photography and the comic strip medium a close-up tightly frames a person or an object. Close-ups are one of the standard shots used regularly with medium shots and long shots. Close-ups display the most detail, but they do not include the broader scene.

BCU = Big Close Up
Big Close Up is often abbreviated to BCU and this term appears in a script, storyboard or shotlist to describe the size of the shot. It usually relates to a person but can sometimes refer to other objects as well.

http://www.eyefish.tv/dictionary/big-close

For a shot of a person, a BCU will include the eyes and mouth but not the whole head as shown above.

http://images.meredith.com/lhj/images/2006/04/ss_100484835.jpg

ECU = Extreme Close Up
The shot is so tight that only a fraction of the focus of attention, such as someone's mouth, can be seen.

http://longbowbusiness.com/wp-content/uploads/pronounce.jpg