Hello! In modern PHP, the garbage collector (GC) is not a mandatory component, provided that the code is written without circular dependencies. As soon as an object loses its last reference (i.e., its reference count reaches zero), PHP immediately frees the resources. In this sense, you can think of PHP as similar to C++.
Assigning NULL to a variable is essentially an explicit destruction of the reference. This can be useful in some cases, such as in a long-running application where the function scope will not be exited for a long time. However, in typical scenarios, it only clutters the code with an unnecessary instruction. --- Ed.
