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By James N Hitz
Repetition(Iteration) Control Structures
Repetition causes a loop. So Iteration constructs are also called Looping Contructs. In looping, a statement block is repeated over and over and over... so many times it may go on forever causing your computer's processor to spin, get a titanic headache and shut down in protest! Poor thing.
We therefore need to be very careful how we structure our code so that we don't create endless loops. Our iteration construct MUST be able to terminate itself.
Iteration in PHP is achieved using any of the following constructs: