TypeScript offers a sliding scale of how much or how little effort you want to put into your declarations: the more effort you put in, the more type safety and code intelligence you get. You will begin this course by learning the fundamentals of TypeScript and eventually move toward advanced concepts. You'll learn how TypeScript relates to JavaScript that you might have written before. You'll understand the benefits of TypeScript and how helps you to avoid software defects. We will learn to use type guards, check null and undefined, create tagged union types, and compare the performance of algorithms. You'll use TypeScript to build a weather forecast widget with Angular, and then build a note-taking client/server application using Angular, Node.js, and MongoDB. Finally, you will create a real-time chat application with React.