In this chapter, we will use the same technologies as in Chapter 1, TypeScript Basics:

• TypeScript playground: This is a website at https://www.typescriptlang.org/play/, which allows us to play around with and understand the features in TypeScript without installing it.
• Node.js and npm: TypeScript and React are dependent on these. You can install them from https://nodejs.org/en/download/. If you already have these installed, make sure npm is at least version 5.2. 

• TypeScript: This can be installed via npm, entering the following command in a terminal:

npm install -g typescript

• It is important that we are using TypeScript 3 in this chapter. You can check your TypeScript version by using the following command in a terminal:

tsc -v

If you need to upgrade to the latest version, you can run the following command:

npm install -g typescript@latest

• Visual Studio Code: We'll need an editor to write our React and TypeScript code. This one can be installed from https://code.visualstudio.com/. We will also need the TSLint (by egamma) and Prettier (by Estben Petersen) extensions installed in Visual Studio Code.