Kotlin File vs Class. Whats the difference?

Issue

Just started using Kotlin and created some activities as Kotlin Files. They work, but still, I want to know what the difference between creating a File and a Class.

Solution

Kotlin Class: Android Studio displays it with no extension if the file contains ONLY ONE class.

Unlike Java, Kotlin allows you to put certain things outside the class like:

• extension functions
• constants

If you, therefore, add any of the above or another class to the file, Android Studio will change it to "Kotlin File":

with extension .kt

Removing the above extras, will again show the file as "Kotlin Class"

Answered By - Maciej Beimcik