object oriented programming php

1<?php
2class Parent {
3	public function __construct() {
4    	echo "Parent Created\n";
5    }
6  	public function sayHello() {
7    	echo "Hello, from Parent\n";
8    }
9  	public function eitherHello() {
10    	echo "Hello, from Parent and child if desired\n";
11    }
12}
13class Child extends Parent {
14	public function __construct() {
15    	echo "Child Created\n";
16    }
17  	public function sayHello() {
18    	echo "Hello, from Child\n";
19    }
20}
21$p = new Parent();	// Parent Created
22$c = new Child();	// Child Created
23$p->sayHello(); 	// Hello, from Parent
24$c->sayHello();		// Hello, from Child
25$p->eitherHello();	// Hello, from Parent and child if desired
26$c->eitherHello();	// Hello, from Parent and child if desired
27?>

1The  PHP Object-Oriented Programming concepts are:
2Class 
3Objects
4Inheritance
5Interface
6Abstraction
7Magic Methods

1Well Explained in here: 
2https://www.androidhive.info/2012/05/how-to-connect-android-with-php-mysql/
3@Zenonymous

1<?php
2   class Mobile {
3      /* Member variables */
4      var $price;
5      var $title;
6      /* Member functions */
7      function setPrice($par){
8         $this->price = $par;
9      }
10      function getPrice(){
11         echo $this->price ."
12";
13      }
14      function setName($par){
15         $this->title = $par;
16      }
17      function getName(){
18         echo $this->title ."
19";
20      }
21   }
22$Samsung = new Mobile();
23$Xiaomi = new Mobile();
24$Iphone = new Mobile();
25$Samsung->setName( "SamsungS8 );
26$Iphone->setName( "Iphone7s" );
27$Xiaomi->setName( "MI4" );
28$Samsung->setPrice( 90000 );
29$Iphone->setPrice( 65000 );
30$Xiaomi->setPrice( 15000 );
31Now you call another member functions to get the values set by in above example
32$Samsung->getName();
33$Iphone->getName();
34$Xiaomi->getName();
35$Samsung->getPrice();
36$Iphone->getPrice();
37$Xiaomi->getPrice();
38?>
39

1public className{
2	public function __construct(){
3    //CODE HERE
4    }
5}