here is what i know. add what you think is interesting.
Music is short for latin word musica, which means entertainment of the muses.
this word evolved from anything that entertained the muses, such as talking, to specifically music as we know it today
music used to be studied as a math, with proportions of the length and how taught a chord was to the note played.
music also used to be used as entertainment, as it is used today.
music also used to be used to stimulate the mind before learning.
Music can be defined as a sound that one defines entertaining, thus something you may call "not music", if it is appreciated by anyone, even the creator, it is considered music.