What is the difference between exit and die in PHP?

Good question, about the use of exit or die you can use one or the other interchangeably, although it is not a bad idea to use one when you want to return an error message and the other when you simply want to execute the stop of a script. It’s a good way to keep your code more organized. The use of parentheses would make sense if you are going to use the returned value for something, for example print an error message or return an int value to end with an error code, although this will not be printed. I don’t know if this clears up any doubts for you … All the best