Oscillators are circuits that generate electrical signals of a specific frequency. They are used in a variety of applications such as radios, watches, and clocks as well as for other tasks. Oscillators work by taking a small amount of energy and turning it into an oscillating signal. This signal is then filtered and amplified to produce the desired frequency. Oscillators are commonly used in electronic circuits because they can produce a wide range of frequencies with a small amount of energy input. Oscillators are also used to control the frequency of signals in communication systems.