what does override mean in java

// A Simple Java program to demonstrate
// Overriding and Access-Modifiers
  
class Parent {
    // private methods are not overridden
    private void m1()
    {
        System.out.println("From parent m1()");
    }
  
    protected void m2()
    {
        System.out.println("From parent m2()");
    }
}
  
class Child extends Parent {
    // new m1() method
    // unique to Child class
    private void m1()
    {
        System.out.println("From child m1()");
    }
  
    // overriding method
    // with more accessibility
    @Override
    public void m2()
    {
        System.out.println("From child m2()");
    }
}
  
// Driver class
class Main {
    public static void main(String[] args)
    {
        Parent obj1 = new Parent();
        obj1.m2();
        Parent obj2 = new Child();
        obj2.m2();
    }
}

Overriding is a feature that allows a subclass or child class to provide a specific implementation of a method that is already provided by one of its super-classes or parent classes.