In things like NCIS they often refer to burn phones.I'm assuming that they are unregistered pay as you go type phones.Does anyone know for sure? And is burn an acronym,like B (?) UnRegistered Number.
Burn is US slang for throwaway or discard. In poker the term 'burn card' is used to describe when after shuffling the top card of a deck is placed on the bottom in case it has been seen.
Burn phones have prepaid minutes and are bought for cash so there is no paper trail of ownership meaning it can be discarded (burned) with little chance of it being traced back to you.