What is the purpose of an oscillator?

Oscillator- Another important circuit like an amplifier in electronics. It is the circuit which generates alternating voltage. For this, it requires direct current ( d.c. ) power supply.
Purpose of an oscillator-
Sinusoidal or non sinusoidal waveform of low or high frequency can be generated by an oscillator.
Applications of an oscillator-
Oscillator is widely used in radio transmitter and receiver, TV transmitter and receiver, audio generator, RF generator, waveform generator, function generator, telemetering, in radio telephony as carrier, in radio telegraphy, in induction heating, in dielectric heating, in remote control, in digital clock, To produce ultrasonic waves, To produce accurate time base and many other electronic equipments.