I leaned that there is copyright for dances, plays, and books. I learned that copyright used to last for fourteen years, then a lifetime and seventy years after death and for a company, one hundred years. I also learned that you can use something that has copyright if you teach with it, use it in the news, or a in a parody, and as a critical comment. Copyrights includes the nature, amount used, and market value of a idea, product or performance.