Music

Dictionaries and encyclopedias define music as "an artistic form of auditory communication incorporating instrumental or vocal tones in a structured and continuous manner."
It is also defined as "any pleasing and harmonious sound"
Technically, music is seen as the arrangement of sounds with respect to rhythm, tone, pitch and dynamics

Rhythm

Rhythm is the arrangement of sounds and silences in time
• Time Signature (Meter) – The arrangement of beats in regular groupings called measures or bars
• Tempo – Tempo is the speed of the beat; the basic piece of music

Pitch

Pitch is the frequency of a note. It refers to how high or low a note sounds
The standard of measurement is A4 (440Hz)
The range of a standard keyboard is 27Hz – 4186Hz (A0 – C8); within the audible range of the human ear

Dynamics

Dynamics refers to the degree of softness or loudness in music
Dynamics is related to the amplitude of vibration

Tone

The quality that distinguishes different types of sounds even when on the same pitch is called tone (timbre)
The unit of measurement of tone is color, described as bright, dark, brilliant, mellow or rich e.t.c.