A "theme song" is a piece of music that serves as an identifying element for a film, TV show or an event. However, there are many other words and expressions that can be used to describe a "theme song," such as opening music, title track, signature tune, anthem, melody or soundtrack. The "theme song" is designed to draw in viewers or listeners, and it usually contains memorable lyrics and a catchy tune that stays in listeners' minds. Although it may be a brief piece of music, it has the power to create a strong emotional connection with its audience and can be the defining feature of a production.