Different theatres define prop differently, but in general, it is any item that is handled and moved by an actor on stage. Sometimes theatres classify props such as hand props meaning that an actor handles the prop with his or her hands. Then there are costume props meaning that the item is added onto the costume at some point during the show. Sometimes if a prop is kept in an actors costume, such as a pocket watch or money that the actor uses, these are referred to as personal props.
The Oxford English Dictionary says that the first use of the word prop was found in 1911. However, the plural, props was first used in 1841. The word properties (spelled as propyrtes) is first found in the 1425 morality play The Castle of Perseverance. Of course, even though the word properties did not appear until late in the first half of the 19th century, stage properties had been used since ancient Greek theatre.
The origin of the word property comes from the Middle English proprete meaning possession, attribute, or what is one's own. There are different theories as to how the word property originated use in theatre. Some think that during the renaissance in Europe, actors would mainly provide their costumes and items used on stage. However, sometimes the theatre companies provided items used on stage and these items were thought to be company properties. Others think it is simply because the items "belong" to the actor that is on the stage, so it would be the actor's property.
Some theatres even hire property managers who are in charge of finding or making props, maintaining the props, and making sure that the props are in their proper places. However, this is not always a position that is in the theatre and actors should always try to keep their props where they belong and to treat them in a way that the least damage (which is hopefully none) will come to them.
The most expensive theatre prop, at least as of April 16, 2002, was the flying car for Chitty Chitty Bang Bang. It cost $1.07 million U.S. to make. A couple of the most recognizable props in theatre are Mary Poppins' umbrella and the magic lamp in Aladdin.
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