# Extensions in Kotlin

DevFeed: [Extensions in Kotlin](<https://devfeed.tech/articles/extensions-in-kotlin-39331.md>)

Original publisher: [Read original article](<https://kt.academy/article/kfde-extensions>)

Published: 2023-10-09T00:01:00Z

Content type: tutorial

Language: en

Sources: [Kt. Academy](<https://devfeed.tech/sources/kt-academy.md>)

Topics: [Kotlin](<https://devfeed.tech/topics/kotlin.md>), [Extension](<https://devfeed.tech/topics/extension.md>), [class](<https://devfeed.tech/topics/class.md>), [Code](<https://devfeed.tech/topics/code.md>)

Tags: [bytecode](<https://devfeed.tech/tags/bytecode.md>), [extension](<https://devfeed.tech/tags/extension.md>), [extension-function](<https://devfeed.tech/tags/extension-function.md>), [kotlin](<https://devfeed.tech/tags/kotlin.md>), [static](<https://devfeed.tech/tags/static.md>), [workshop-learning-programming](<https://devfeed.tech/tags/workshop-learning-programming.md>)

## AI overview

This tutorial explains Kotlin extension functions and properties, including how they are defined, called on receiver instances, and used with types from external APIs. It also examines their JVM implementation, where an extension receiver becomes a regular parameter in a static function.

## Source excerpt

What are extensions in Kotlin and how do we use them.