A popular pastime, amusement or diversion. For example, doing the daily crossword puzzle is a great form of entertainment for many people.
Entertainment is a highly diversified industry and a multi-billion dollar business that spans across all media platforms. Some forms of entertainment have proven to be extremely versatile and adaptable to various contexts, for instance music that can be adapted from the stage or personal usage; films that can be adapted to a screen of any size or scale; or books that can be re-written for new generations.
Many kinds of entertainment touch on themes that the brain was evolved to deeply respond to. These include murder, backstabbing and other things that we find entertaining because they are true to life.