(Mary and her classmate Alex are off from school. They are going to see a film.)
Mary: Do you have the time, Alex?
Alex: It's 7:20.
Mary: We are early. The film starts at 7:30. Let's have something to drink.
Alex: That's a good idea.
Mary: Something smells good.
Alex: Right, that's popcorn. Would you like some popcorn?
Mary: Yes, I'd love some. Do you know who invented popcorn?
Alex: It is said that popcorn is a delicacy that was developed by the Indians of North America.
Mary: When did they invent it?
Alex: It has been dated back thousands of years.
Mary: I see.
Alex: Do you know that the Indians were not only eating popped corn, but they also used popped corn in headdresses, necklaces and in religious ceremonies?
Mary: Yes, we have seen these in some films and according to most sources, a deerskin bag full of popcorn was served at the first Thanksgiving dinner at Plymouth Rock in 1621.
Alex: You know, popcorn's popularity grew during the Depression of the 1930s when people realised that a little popcorn could go a long way. But its success was clinched when movie theatres across the continent started serving the snack. By 1947, 85 per cent of movie houses were selling popcorn at their concession stands.
Mary: Oh, the movie's about to start. Let's go.