Intended Readership: MUSIC LOVERS, MUSICIANS
There are 2 parts to music copyright – Song Copyright and Sound Recording Copyright.
Song Copyright
The song copyright belongs to the writer of the song and / or a publisher. The song copyright, annotated with © or “Copyright” on a CD, is accordingly divided into 2 equal parts – the writer share and the publishing share. The publisher essentially represents the writer to aggressively exploit all commercial opportunities for the music. So the writer focuses on writing the music while the publisher is like an agent sniffing out opportunities – licensing, motion pictures, TV, advertising etc. to monetize the work.
The writer share of the copyright typically stays with the writer for life while the publishing rights are assigned to a publisher for a specific time frame. For example, Universal Music Publishing has in 2009 secured the publishing rights (non-US) for the Jimi Hendrix Catalog for a period of 5 years. (A more detailed section on publishing will be covered in a subsequent chapter)
Sound Recording Copyright
The sound recording copyright represents the copyright for a “specific” recording of the song. This is normally held by the record company which has signed on an artist to record a song. It is annotated with a ℗ (“P” in a circle) on the CD.
[Geek Alert: An easy analogy for software programmers with OOPS (Object Oriented Programing). The Song Copyright "©" represents the Class. A Class can have many Instances and each Instance has an associated Sound Recording Copyright "℗" held by the creator of the instance. Sweet huh?]
So the next time you hold an audio CD case, turn it over and stuff that looked like gibberish earlier, suddenly makes perfect sense. If you want use a song commercially, you would need a clearance from all copyright holders. Very often youtube clips are removed for copyright violation. Now you know why. That beautiful background song you added to the video of your cats has a song copyright and a sound recording copyright.

Image Copyright Arun Shenoy. The album art clips used are purely for illustration and copyright of their respective owners.
Term of Copyright
A lot of folk are confused about this and classify much music as “public domain”. The reality is quite different. A copyright runs for the author’s life plus 70 years after his death. 70-year period is measured from the date of the death of the last surviving collaborator. So sorry folks, unless you plan to outlive the last member of the Beatles by 70 years, you will not be able to use the Beatles music for free. Don’t worry. Maybe I will let you use mine
Cover songs
Very often, you see famous songs covered by famous bands (and the not so famous ones too). So how does what I have explained above work? Here is a short schematic.