There are two types of circuit breaker - actually there's more than two types but no matter.
An RCD usually controls all the power and lighting circuits. It measures the current difference between Live & Neutral and if it exceeds 30mA (usually 30mA) it will trip - the assumption being that the "missing" current may be passing through a person - a safety device to prevent electrocution. RCD stands for residual current device and RCDs have two poles - Live & Neutral.
An MCB or miniture circuit breaker has just one pole and limits the current through a particular circuit - downstairs lights or upstairs power etc. Too much current on the circuit and the breaker will trip. They protect the house wiring and prevent wires overheating and catching fire and the house burning down.
When a fillament lamp fails the broken pieces of the fillament sometimes fall across the metal supports of the fillament and cause a brief overcurrent - this causes the MCB to trip.
In my house candle shaped bulbs are the worse culprits for tripping breakers - then regular bulbs that point upwards.
It is not unusual for an MCB to trip when a lamp fails but it is relatively rare for and RCD to trip for a blown bulb.
Peccavi
March 2010