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About Kotlin

Kotlin was designed and developed by JetBrains, the company behind IntelliJ. It is a language that runs on the JVM which can target versions 6+ (including the Android platform). JetBrains wanted to use a statically typed language which can remove Java boilerplate code, provide modern functional paradigms, and had seamless two-way Java interoperability with their existing codebase. The JVM already had alternate languages like Groovy and Scala but neither fit the bill with their desired criteria, so they built Kotlin.

Kotlin syntax is similar to Scala and Swift but pulls in the best-of-breed features from other languages such as C# and Groovy. Kotlin took a pragmatic approach at features included in the language by only providing functionality that has been proven to be useful for developers. With this decision they implemented a subset of features of Scala with the intent that it will provide more maintainable code with an easier learning curve for developers looking for a "better Java".

JetBrains has a dedicated team of developers working on Kotlin with the codebase available on Github.

fun getGreeting(): String {
    return "Hello, World!"
}

Key Features of Kotlin


Kotlin

Pragmatic

Kotlin is trying hard to be a modern language with great tooling support.

Statically Typed

Strong type-safety and null-safety features for building robust software.

Multi-Paradigm

Kotlin support both functional and mainstream OOP programming principles.

Platform Independent

Develop for Android, iOS, JVM, Node.js, browser and many native targets.

Garbage collected

Kotlin (as a modern generic-purpose language) does memory management for you.

Open-Source

Kotlin is fully open-source. Submit patches or suggest language improvements.

Get mentored the Kotlin way

Every language has its own way of doing things. Kotlin is no different. Our mentors will help you learn to think like a Kotlin developer and how to write idiomatic code in Kotlin. Once you've solved an exercise, submit it to our volunteer team, and they'll give you hints, ideas, and feedback on how to make it feel more like what you'd normally see in Kotlin - they'll help you discover the things you don't know that you don't know.

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Community-sourced Kotlin exercises

The Kotlin track on Exercism has 89 exercises to help you write better code. Discover new exercises as you progress and get engrossed in learning new concepts and improving the way you currently write.

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Kotlin

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