A music apparatus has a capability of using a composite music content. In
the music apparatus, a storage section stores a file of the composite
music content composed of a plurality of content materials, each of which
is encrypted individually. The content materials include a usable content
material which matches with the capability of the music apparatus and an
unusable content material which does not match with the capability of the
music apparatus. In the music apparatus, an identifying section
identifies the usable content material among the plurality of the content
materials of the composite music content stored in the storage section.
Then, a decrypting section selectively decrypts the usable content
material identified by the identifying section. Thereafter, a using
section uses the decrypted usable content material.
