Static function in PHP

In some cases, it is very convenient to access methods and properties from the point of view of the class, not the object. This can be done using the statickeyword. Any method declared static is accessible without creating an object. Static functions are associated with a class, not an instance of a class. They are only allowed access to static methods and static variables. To add a static method to a class, use the static keyword.

public static function test() {// Method implementation} 

They can be called directly outside the class using the scope resolution operator visibility (: