For the purposes of this Act, "copyright " means the exclusive right subject to the provisions of this Act, to do or authorise the doing of any of the following acts in respect of a work or any substantial part thereof, namely:—

1. in the case of a literary, dramatic or musical work, not being a computer programme,—
2. in the case of a computer programme,—
3. in the case of an artistic work,
4. in the case of a cinematograph film,
5. in the case of a sound recording,—