Let us choose if we saw the "regular version" or the "alternate version" of a movie or episodes.
like theatrical cut, extended cut, director's cut, workprint, fanedit or what else
Movie Avatar: www.imdb.com/title/tt0499549/alternateversions
Series Hannibal: http://www.imdb.com/title/tt2243973/alternateversions
This is very important for shows like "QI XL" and "Have I got A Bit More New For You" where the running times are different, and it affects all the stats.