Why are propeller airplanes still made? Airplanes with propellers were invented a long time ago. After that, jet engines came into existence. My question is: why do we still have propeller engines?

The reasons I can think of are:


They are cheaper;
They cannot achieve very high speed;
They are not very noisy (though not always).


Besides these, are there any other reasons general aviation airplanes built nowadays don't have jet engines?
Jet engines are only efficient at high altitudes and high speed (25,000+ feet or so and 300+ knots or so true airspeed).  The cost of making and operating an airplane capable of flying there is very high, and most general aviation flights have no need of such performance (or expense) hence, propeller airplanes.

Reciprocating engine propeller airplanes are relatively efficient at low altitudes and airspeeds, they are more economical for the average types of general aviation flights.  They are also much cheaper to build and operate than a turbine powered airplane.

Turboprops fill the efficiency gap between reciprocating and pure jet engines, being most efficient at mid altitudes and airspeeds.  Still more expense and performance than most general aviation flights need though.