Kotlin
Modern, concise, JVM-powered
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read 7 chapters Programming language
Created
2011 by JetBrains
Type
Static, JVM-based, null-safe
Current version
Kotlin 2.0 (2024)
Powers
Google's preferred Android language
Key feature
Null safety + coroutines
Interops with
Java (100% compatible)
File extension
.kt
Best for
Android, JVM backends, multiplatform
What is Kotlin?
Kotlin is a modern programming language created by JetBrains in 2011. Since 2019, it's Google's preferred language for Android development. It's fully interoperable with Java.
Why Kotlin?
Kotlin eliminates Java's verbosity while keeping its power. Null safety catches NullPointerExceptions at compile time, and coroutines make async code readable.
| Feature | Kotlin | Java | Swift |
|---|---|---|---|
| Null safety | Built-in | Manual checks | Optionals |
| Verbosity | Concise | Verbose | Concise |
| Android | Preferred | Supported | N/A |
| Coroutines | Built-in | Virtual threads (21+) | N/A |
| Learning curve | Medium | Medium | Medium |
What you'll learn
| Chapter | What you'll know |
|---|---|
| Introduction | What Kotlin is, variables, types |
| Null Safety | Nullable types, safe calls, let |
| Classes | Data classes, sealed classes, interfaces |
Start with introduction.