<Dl> <Dd> Some theaters (including those with IMAX stadiums) have detectors at the doors to pick up recording smugglers . At particularly anticipated showings, theaters may employ night vision equipment to detect a working camera during a screening . In some jurisdictions this is illegal unless the practice has been announced to the public in advance . </Dd> </Dl> <Dd> Some theaters (including those with IMAX stadiums) have detectors at the doors to pick up recording smugglers . At particularly anticipated showings, theaters may employ night vision equipment to detect a working camera during a screening . In some jurisdictions this is illegal unless the practice has been announced to the public in advance . </Dd> <Ul> <Li> Crowd control: As movie theaters have grown into multiplexes and megaplexes, crowd control has become a major concern . An overcrowded megaplex can be rather unpleasant, and in an emergency can be extremely dangerous (indeed, "shouting fire in a crowded theater" is the standard example in American English of the limits to free speech, because it could cause a deadly panic). Therefore, all major theater chains have implemented crowd control measures . The most well - known measure is the ubiquitous holdout line which prevents ticket holders for the next showing of that weekend's most popular movie from entering the building until their particular auditorium has been cleared out and cleaned . Since the 1980s, some theater chains (especially AMC Theatres) have developed a policy of co-locating their theaters in shopping centers (as opposed to the old practice of building stand - alone theaters). In some cases, lobbies and corridors cannot hold as many people as the auditoriums, thus making holdout lines necessary . In turn, ticket holders may be enticed to shop or eat while stuck outside in the holdout line . However, given the fact that rent is based on floor area, the practice of having a smaller lobby is somewhat understandable . </Li> </Ul> <Li> Crowd control: As movie theaters have grown into multiplexes and megaplexes, crowd control has become a major concern . An overcrowded megaplex can be rather unpleasant, and in an emergency can be extremely dangerous (indeed, "shouting fire in a crowded theater" is the standard example in American English of the limits to free speech, because it could cause a deadly panic). Therefore, all major theater chains have implemented crowd control measures . The most well - known measure is the ubiquitous holdout line which prevents ticket holders for the next showing of that weekend's most popular movie from entering the building until their particular auditorium has been cleared out and cleaned . Since the 1980s, some theater chains (especially AMC Theatres) have developed a policy of co-locating their theaters in shopping centers (as opposed to the old practice of building stand - alone theaters). In some cases, lobbies and corridors cannot hold as many people as the auditoriums, thus making holdout lines necessary . In turn, ticket holders may be enticed to shop or eat while stuck outside in the holdout line . However, given the fact that rent is based on floor area, the practice of having a smaller lobby is somewhat understandable . </Li>

When did the first it movie come out in theaters