This document provides an overview of the Kotlin programming language. Kotlin was developed by JetBrains starting in 2010 as a better alternative to Java that runs on the JVM. It has gained popularity due to its interoperability with Java and support from Spring. The Kotlin community has grown significantly since its 1.0 release in 2016 and it is currently used in many JetBrains products and by developers for both server-side and Android applications.