continue is used within looping structures to skip the rest of the current loop iteration and continue execution at the beginning of the next iteration.
Note: Note that in PHP the switch statement is considered a looping structure for the purposes of continue.
continue accepts an optional numeric argument which tells it how many levels of enclosing loops it should skip to the end of.
Omitting the semicolon after continue can lead to confusion. Here's an example of what you shouldn't do.