I don't know of any links, so I'll give this a shot.
most breakers that you're likely to encounter are thermal-magnetic.
The thermal part has a bi-metallic strip. Since the 2 metals expand & contract at different rates, the strip will bend as it heats up. If it bends enough, it will engage a trip mechanism and turn off the current. This is for overloads.
The magnetic part consists of a small coil in series with the load. When enough current flows, the magnetic field is strong enough to acuate the trip mechanism. This part is for short circuits, ground faults or any other large current flow.
Tom
