What causes a circuit to oscillate? What limits the amplitude of oscillation?

Describe the phase shift oscillator. How is its frequency determined?

Describe the Colpitts oscillator. How is its frequency determined?

How does a square wave generator differ from the two types of oscillators above?

Why is negative feedback considered to be more important than positive feedback?

What is the basic rationale for using negative feedback?

What practical benefits arise from the use of negative feedback in an amplifier circuit?

How is negative feedback used in the common emitter transistor amplifier? the emitter follower?