In this video we will discuss, how to implement abstract classes concept in JavaScript. Object oriented programming languages like C# and Java, support abstract classes. Abstract classes are incomplete. So, trying to create an instance of an abstract class raises a compiler error. Abstract classes can only be used as base classes. Let us first look at a simple C# example. 1. Open visual studio and create a new empty asp.net web application project. 2. Add a webform to the project. Name it WebForm1.aspx.