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Kotlin Introduction

What is Kotlin?

Kotlin is a modern, trending programming language that was released in 2016 by JetBrains.

It has become very popular since it is compatible with Java (one of the most popular programming languages out there), which means that Java code (and libraries) can be used in Kotlin programs.

Kotlin is used for:

  • Mobile applications (specially Android apps)
  • Web development
  • Server side applications
  • Data science
  • And much, much more!

Why Use Kotlin?

  • Kotlin is fully compatible with Java
  • Kotlin works on different platforms (Windows, Mac, Linux, Raspberry Pi, etc.)
  • Kotlin is concise and safe
  • Kotlin is easy to learn, especially if you already know Java
  • Kotlin is free to use
  • Big community/support

Get Started

This tutorial will teach you the very basics of Kotlin.

It is not necessary to have any prior programming experience.

Get Started »

What is Kotlin? How and what is Kotlin used for?

Kotlin - is a modern, cross-platform, statically typed, universally typed programming language that runs on top of the JVM (Java Virtual Machine). Kotlin is designed to fully interact with Java. The version of the Kotlin standard library for the JVM depends on the Java Class Library, but thanks to type inference, the Kotlin syntax can be more concise.

Kotlin was developed by JetBrains in 2011, which is also the creator of such popular IDEs as IntelliJ IDEA and Android Studio. The creation of the Kotlin language was motivated by the desire of developers to create a programming language that would be safer, more efficient and more concise than the Java programming language. Kotlin has many advantages, such as asynchronicity, object-oriented approach, functional programming, ideal for testing, etc.

Kotlin is used to develop mobile applications, web applications, server applications, games, software and many other projects. Kotlin is Google's first choice for Android app development.

Here are some examples of web projects that have been developed using Kotlin:

  • Trello: an online project management tool
  • Coursera: an online learning platform
  • Evernote: program for keeping notes
  • Pinterest: a social network for storing and sharing ideas

What is the Kotlin language for?

Kotlin can be used to build a variety of software products, such as:

  • Mobile apps for Android. Kotlin is the official development language for Android and is actively used to create modern mobile applications.
  • Services and websites. Kotlin can be used to create websites and web services, as well as to develop the backend of such applications.
  • Desktop applications. Kotlin can be used to create desktop applications for Windows, macOS, and Linux.
  • Corporate programs. Kotlin can be used to create corporate applications, such as management systems, CRM systems, etc.

As you can see, Kotlin is used to develop various projects. This allows developers to create software faster and more efficiently, while maintaining high-code quality.

Kotlin's history

The Kotlin language was created in 2010 by the JetBrains development team. The goal of the new programming language was to create more secure, performant, and readable code than was the case with Java.

In 2011, Kotlin was publicly introduced at the JetBrains conference, and in 2016, Google announced Kotlin as the official development language for Android.

Why should you learn Kotlin?

Kotlin has a number of advantages that make it an attractive language to learn:

  • Productivity. Kotlin allows you to write code more compactly and expressively, which speeds up the development process
  • Security. Kotlin has a number of tools to ensure code safety, which helps avoid compile-time errors
  • Readability. Kotlin code is written in a more human-friendly form, which makes it easier to read and maintain

What has already been built with Kotlin?

Many software products have been built using Kotlin, such as:

  • Websites: Twitter, JetBrains, GitHub
  • Mobile Apps: Uber, Pinterest, Evernote
  • Desktop applications: Visual Studio Code, IDEA IntelliJ, Android Studio
  • Corporate applications: Spotify, Netflix, Slack

What can you build with Kotlin?

Any software product that can be built with Java can be built with Kotlin. Here are some examples:

  • Computer and mobile games
  • Medical programs
  • Programs for communication
  • Programs for the economy
  • Programs for science


Kotlin is a modern, powerful and secure programming language that has a wide range of applications. It is a good choice for developers who want to create high-quality and efficient software products.