Operations on classes and objects in php

$p1 = new Person('michael');//Pass the name to the constructor __construct of the Person class

echo($p1->name);//Get the public instance attribute name of object p1 (note there is no $)

$p1->speak();//Call the instance method speak

echo(Person::$sex);//Get the class variable (static $sex)

echo(Person::sex);//Get the constants in the class (not static const, no static const. Only class variables and no class constants.)

Person::run();//Call class method (or static method static function)

Summary:

　 Used for object instance operations ->

　For class operations::