Need Explanation "Crystal Oscillator"

Below is a circuit,
I need explanation that how it start to oscillate.
Plz tell me step by step procedure.

A small amount of noise from the transistor or resistors or just the "click" from power being applied gets amplified by the transistor and is phase-shifted 180 degrees by the crystal and its two capacitors, causing the feedback to be positive. The positive feedack is at the frequency passed by the crystal and keeps the oscillation going.

Thanks audioguru .

what the crystal gives 180 degrees Phase Shift???

Any crystal operating at its resonant frequency.

I sense one of these 20 questions threads comming on.

Ayne,
Asking questions is good but many of the ansers and be found by reading articles this this article, so please read it before asking any more questions.

Didn't you read about crystal oscillators in Google? There are many articles that explain the phase-shift from a crystal in an oscillator.

I forgot to say that the transistor is an inverting amplifier that provides the other 180 degrees phase-shift. So the total amount of phase-shift is 360 degrees.