A copyright is defined by the Canadian Intellectual Property Office (CIPO) as " the exclusive right to copy a creative work or allow someone else to do so." It applies to original literary, dramatic, musical and artistic works (including computer programs) as well as sound recordings. performers performances and communication signals.
Copyright generally exists automatically when an original work is created and is protected under copyright common law, so registration with CIPO is not necessary. However, given the nominal fee, it is still beneficial to register as a) you receive a certificate which can be used as evidence of ownership and b)it helps others find the owner of a copyright.
An individual or corporation can register a copyright online or by downloading and mailing; the fees are $50 and $65 respectively. This is a one time fee and no renewal is necessary. CIPO encourages you to file the application online as it is faster (and cheaper).
Additional info available here.