We will show you how to get Kotlin running and start writing some code. It is very simple, especially if you already were working with Java and IntelliJ Idea.
The previous example was executed using only Java and Kotlin compiler. To get it running and execute commands from example you need to install Java and Kotlin compiler. Latest versions of both may be found on Orcale (Java) and Kotlinlang (Kotlin) websites.
For more serious programming we will need an IDE. In this book (and probably in any future development) you will use IntelliJ Idea, IDE developed by creators of Kotlin, JetBrains Company.
Download and install IntelliJ Idea Community Edition. When it's done, from IDE preferences install support for Kotlin language with all plugins that are coming with it. When done, you are ready to start writing some code.