Kotlin was created by JetBrains, the company behind IntelliJ IDEA, starting development in 2010 and publicly unveiling the language in 2011 — named after Kotlin Island near St. Petersburg, where much of the team worked, following Java's tradition of naming languages after places. It reached its stable 1.0 release in February 2016, fully interoperable with existing Java code and libraries while directly addressing pain points JetBrains' own engineers experienced writing Java daily, most notably null pointer exceptions. Google announced first-class Android support at I/O 2017, then declared Kotlin its preferred language for Android development in 2019 — a turning point that drove much of Kotlin's widespread adoption.
Hello, World — noticeably less ceremony than Java
No class wrapper is required for a simple entry point, no semicolons are needed, and fun replaces Java's much longer method declaration syntax — small differences that add up across a real codebase.
fun main() {
println("Hello, World!")
}Full interoperability with Java, in both directions
Kotlin compiles to the same JVM bytecode Java does, meaning Kotlin code can call existing Java libraries directly, and Java code can call Kotlin code just as easily — this bidirectional interop is precisely why teams could adopt Kotlin incrementally in existing Java codebases rather than needing a full rewrite.
Beyond Android: genuinely multiplatform today
While Android remains Kotlin's most visible use case, Kotlin Multiplatform (KMP) lets the same business-logic code target Android, iOS, backend servers, and web from one shared codebase — as of Kotlin 2.4 (June 2026), this multiplatform story has matured considerably, with faster builds, smaller binaries, and improved Native/iOS interop specifically highlighted as focus areas.