Britannica online referenced below describes the saxophone’s range which can be from soprano to double bass and consists of a conical metal tube which has finger keys.
The article goes further to say that the first saxophone invented was patented by Antoine- Joseph Sax, hence the name Saxophone, and this was in 1846 in Paris.
There are about 24 openings on the Saxophone which are controlled by padded keys. Its mouthpiece is the same as that of a clarinet.
There are also two octave key vents and these are used to allow the saxophone reach a higher octave.
The saxophone fits in well with brasses and woodwinds and is a versatile instrument.
It is popular as a jazz instrument and less popular in the orchestra.
It is a wonderful musical instrument to improvise on and has remained popular.