Pachelbel's Canon is an extraordinary piece of music. Most people couldn't name it yet almost everyone knows it because it is one of the most used pieces in weddings, commercials, films, classical music radio play lists and compilation albums.
Canon is a musical term for a type of composition which involves a repeated melody in different voices. A familiar type of canon is called a round, examples of which are 'Frère Jacques' and 'Row, Row, Row Your Boat'.
For a more complete explanation go to
Canon on Wikipedia.
On YouTube you can find many interpretations of the Canon. One of the most viewed (over 65 million views when I last looked) is JerryC's version.
Here is a link to it:
JerryCs Canon Rock.
And here is an interesting article "Web Guitar Wizard Revealed at Last" about the video and JerrC by
the New York Times.
The video below - Ultimate Canon Rock - is a clever mix of 39 different performers of JerryC's arrangement including JerryC.