Function Of A Music Video

A music video is the way that artists get their music out to an audience. But instead of having their music listened to, as they do on the radio, the music video gives a visual interpretation of the song. 

As everyone usually sees music videos, and companies use this to their advantages and someones use product placement in artists music videos to sell their products to the audience. 

The music video also promotes the single from the album, and it also promotes the artist.
To promote their music, the video has to give the audience a better understanding of the song, entertain the audience with a visual performance and showing the talent of the artist, and sell the song in a way that the audience can remember the song.

A music video that I feel is a great example of this is Justin Timberlake - What Goes Around Comes Around. The song itself is about karma and people getting what they deserve. In the full video, he performs a strong narrative story where he is the participant and the narrator throughout and shows his story through a character. He is telling the story through a performance which also shows the talent of Justin Timberlake. Although he doesn't dance in the video, the video definitely gives the viewer a better understanding of the song itself.