Learn Kotlin

Kotlin is a modern, statically-typed language that runs on the Java Virtual Machine and interoperates directly with existing Java code. It is Google's recommended language for native Android development, and a good choice for anyone who already knows some Java and wants more concise, safer syntax.

What this path covers

25 chapters, in reading order: values and syntax, control flow, functions, collections, objects, error handling, and a small combined project, followed by intermediate topics (debugging, files, APIs, async, project structure, state) and advanced topics (architecture, testing, security, performance, deployment, and a full real-project walkthrough).

Start here

Kotlin foundations — The mental model for reading a program: values, statements, output, and program flow.

Full chapter list

  1. Kotlin foundationsBeginner
  2. Kotlin syntax and data typesBeginner
  3. Kotlin variables and valuesBeginner
  4. Kotlin operators and expressionsBeginner
  5. Kotlin conditions and decisionsBeginner
  6. Kotlin loops and repetitionBeginner
  7. Kotlin functions and reusable logicBeginner
  8. Kotlin arrays, lists, maps, and setsBeginner
  9. Kotlin objects and classesBeginner
  10. Kotlin error handling and debuggingBeginner
  11. Kotlin basic projectBeginner
  12. Kotlin debugging step by stepIntermediate
  13. Kotlin files, JSON, and local dataIntermediate
  14. Kotlin APIs and HTTPIntermediate
  15. Kotlin async programmingIntermediate
  16. Kotlin project structure and modulesIntermediate
  17. Kotlin state managementIntermediate
  18. Kotlin best practices and clean codeIntermediate
  19. Kotlin software architectureAdvanced
  20. Kotlin testing behaviorAdvanced
  21. Kotlin security foundationsAdvanced
  22. Kotlin performance and measurementAdvanced
  23. Kotlin deployment and releaseAdvanced
  24. Kotlin real project walkthroughAdvanced
  25. Kotlin real-world patterns and advanced conceptsAdvanced
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