First, lets start out with a definition of Fair Dealing, and move from there.
Fair Dealing is an exception and limitation to the infringement of copyright and moral rights. The purpose of this exception is to ensure that a person is not unduly restricted in their use or dissemination of a copyrighted work.
Copyright is a complex system with simple goals. It’s the system we use to promote the creation of art, music, books, plays, films, etc. – all the creative products that enrich our cultural life. Ideally, this system strikes a balance between fostering the public interest in the creation and circulation of cultural products, and ensuring compensation for the creators of those products.