Property overloading continues to protect properties by forcing access and manipulation through public methods, yet allowing the data to be accessed as if it were a public property. These methods, known as accessors and mutators, or more informally as getters and setters, are automatically triggered whenever the property is accessed or manipulated, respectively.

PHP does not support multiple inheritances. Implementation of multiple interfaces is supported.

Abstract class: An abstract class is a class that cannot be instantiated. Abstract classes are intended to be inherited by a class that can be instantiated, better known as a concrete class. Abstract classes can be fully implemented, partially implemented or not implemented at all.

Interface: An interface defines a general specification for implementing a particular service, declaring the required functions and constants without specifying exactly how it must be implemented.

Final keywords indicates that the class or method cannot be extended.

Just use the PHP command line interface (CLI) and specify the file name of the script to be executed as follows:
php script.php