Kotlin is a statically typed programming language from JetBrains that runs on the JVM and interoperates fully with Java. Google made it the preferred language for Android, and Kotlin Multiplatform extends a single codebase to iOS, the server and the browser.
Courses here cover the language itself — coroutines and structured concurrency, null safety, extension functions and the type system — along with its use in Android apps and in server-side frameworks such as Spring Boot and Ktor.