Introduction to Kotlin

What is Kotlin?

Kotlin is a modern, concise, statically typed language by JetBrains that runs on the JVM (plus Android, Native and JS). Google made it the preferred language for Android, and Spring supports it first-class.

Why Kotlin Wins Over Java

• Concise - data classes replace 50 lines of POJO boilerplate with one line.
• Safe - null safety is in the type system; entire bug classes vanish.
• Pragmatic - 100 percent Java interoperable; adopt file by file.
• Modern - coroutines make async code read like sync code.

Where Kotlin Runs

• JVM - backend services, Spring Boot, desktop.
• Android - the default language for new apps.
• Multiplatform - share logic across Android, iOS and web.

Kotlin vs Java in One Glance

// Java: 12 lines for an immutable User POJO
// Kotlin:
data class User(val name: String, val email: String)

Key Points

• Kotlin is concise, safe and fully Java-interoperable.
• One language for backend, Android and multiplatform.
• Java developers feel productive within days, not months.