In this free PHP programming course we are taking a look at What is Pass By Reference in PHP, Pass By Reference Explained, Learn PHP Codecademy, Parameter Alias. In this Codecademy section, we are looking at PHP functions, and this lesson specifically goes into pass by reference. We learn that we are able to invoke functions with values directly or variables. When a function is invoked with a variable as its argument, it’s like we are assigning the value that variable holds the function’s parameter. In essence, we are assigning a copy of our variable’s value. When we do this, the argument and variable are distinct entities. This means any changes that are made in the function to the parameter, are not going to affect the variable that we pass in. If we want the changes to be permanent, we can prepend the parameter name with the “&” (reference sign). When we do this, we assign the parameter to be an alias for our argument variable. This means that both the parameter and variable will point to the same spot in memory. This will allow any changes made to the parameter within our function, to permanently change the variable as well. Learn to pass by reference to master PHP programming. Practice pass by reference to truly understand how it works. Understand pass by reference to master programming. Thanks for watching What is Pass By Reference in PHP, Pass By Reference Explained, Learn PHP Codecademy, Parameter Alias.