Dr. Charles Simonyi is the Father of Modern Microsoft Excel                                           JavaScript was originally developed by Brendan Eich of Netscape under the name Mocha, later LiveScript, and finally renamed to JavaScript.                                           The word "Biology" is firstly used by Lamarck and Treviranus                                           Hippocrates (460-370 bc) is known as father of medicine.                                           Galene, 130-200 is known as father of Experimental Physology                                           Aristotle (384-322 BC) is known as Father of Zoology because he wrote the construction and behavior of different animals in his book "Historia animalium"                                           Theophrastus(370-285 BC) is known as father of Botany because he wrote about 500 different plants in his book "Historia Plantarum".                                           John Resig is known as Father of Jquery -                                          HTML is a markup language which is use to design web pages. It was invented in 1990 by Tim Berners-Lee.                                                                The Google was founded by Larry Page and Sergey Brin.                                                                Rasmus Lerdorf was the original creator of PHP. It was first released in 1995.                                                               Facebook was founded by Mark Zuckerberg                                                               Bjarne Stroustrup, creator of C++.                                                                Dennis Ritchie creator of C                                                                                                                              James Gosling, also known as the "Father of Java"                                          At 11.44%, Bihar is India's fastest growing state                                          Father of HTML -Tim Berners Lee                                          orkut was created by Orkut Büyükkökten, a Turkish software engineer                    Photoshop: It came about after Thomas Knoll, a PhD student at the University of Michigan created a program to display grayscale images on a monochrome monitor which at the time was called 'Display'.

Abstract keyword

Abstract keyword used for method declaration declares the methods without implementations.

Abstract class in java have abstract methods that is not implemented in abstract class, but implemented  in subclasses in java program. If  the class in java program is not required to get instantiated than that class use the abstract keyword but this class rather is available for other classes to extend by other classes.

Abstract keyword will be used in  method declaration to declare that method without providing the implementation in that java program. 
In other words we can say that, it formally unfinished class as well as  method,  that marked with the help of keyword abstract.
Defining abstract is a way of preventing someone from instantiating a class that is supposed to be extended first. In java program abstract class is deliberately missing similar to like an interface which will missing all method bodies in the program. Abstract class provides a way to extend an actual class. We will not use new on abstract classes but will use abstract references in the java program, that always point to objects of the class that extends an abstract class.

In java program for practical use of an abstract class, we will define a non-abstract class that extends an abstract one. This will use any of the inherited non-abstract methods.

Most of the time abstract class may extend another abstract class. In that condition it need not implement all in the non-abstract methods. An abstract keyword used both on classes and methods.  In case of class declared with an abstract keyword may not be instantiated that is the only thing that abstract keyword doing. 
Syntact: Abstract Class Syntax
abstract class ClassName
abstract Type MethodName();
Type Method()
/ method body

Example: Declaring an abstract class:
abstract StudentSystem (String name);
If a class is declared abstract type then its methods will be also declared abstract type.

When a method is declared abstract, the method can not have a definition. This is the only effect the abstract keyword has on method.

Here's an example of an abstract method:
abstract int student_id (String name);
Both the abstract classes and abstract methods are skeletons shaped. Abstract keyword defines a structure while without any implementation. In java program an abstract classes have abstract methods but  an abstract class will not necessarily require that methods will also abstract type.

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