Learn Kotlin,
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Clear explanations, real code examples and sample output — from basics to coroutines, OOP and JVM interop.
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Popular Tutorials
async Function in Kotlin
Learn async Function in Kotlin with clear explanation, syntax, example program, sample output, best practices, and FAQs.
Comments in Kotlin
This program describes and demonstrates Comments in Kotlin with sample output,definition,syntax
Coroutine Cancellation in Kotlin
Learn Coroutine Cancellation in Kotlin with clear explanation, syntax, example program, sample output, best practices, and FAQs.
Coroutine Introduction in Kotlin
Learn Coroutine Introduction in Kotlin with clear explanation, syntax, example program, sample output, best practices, and FAQs.
If Statement in Kotlin
This program describes and demonstrates If Condition Statements with sample output,definition,syntax
Dispatcher Main in Kotlin
Learn Dispatcher Main in Kotlin with clear explanation, syntax, example program, sample output, best practices, and FAQs.
Higher Order Function Basics in Kotlin
Learn Higher Order Function Basics in Kotlin with clear explanation, syntax, example program, sample output, best practices, and FAQs.
Annotation Declaration in Kotlin
Learn Annotation Declaration in Kotlin with clear explanation, syntax, example program, sample output, best practices, and FAQs.
Learning track
Kotlin Basics
Everything you need to start writing Kotlin - from your first program to functions, with examples and output for every concept.
Basic Programs
Get started with Kotlin: your first program, variables, and comments.
4 tutorialsKotlin Data Types
Explore Int, Float, Double, Char, Boolean, String and more, with type conversion.
11 tutorialsKotlin Operators
Arithmetic, relational, logical, assignment and Kotlin's special operators.
15 tutorialsConditional Statements
Control program flow with if, when, break, continue and return.
4 tutorialsKotlin Input and Output
Read input and print output in Kotlin, including the Scanner class.
5 tutorialsLooping & Controls
Repeat work with for, while, do-while and the repeat function.
6 tutorialsKotlin Functions
Define functions with default, named and vararg parameters, single-expression, local, tailrec and infix functions.
10 tutorialsLearning track
Kotlin Intermediate
Move beyond basics with null safety, strings, arrays, collections, packages and exception handling.
Null Safety
Nullable types, safe casts, let, lateinit and null handling in Kotlin.
7 tutorialsKotlin Strings
String basics, templates, comparison, substring and raw strings.
6 tutorialsKotlin Arrays
Declare, initialize, access and iterate arrays in Kotlin.
5 tutorialsCollections Intro
Lists, sets, maps and common collection operations.
6 tutorialsPackages & Imports
Organize code with packages, imports and visibility modifiers.
5 tutorialsException Handling
try-catch, finally, throw, custom exceptions and try expressions.
6 tutorialsType Features
Type aliases, destructuring declarations and related Kotlin type syntax.
2 tutorialsLearning track
Object Oriented Kotlin
Classes, inheritance, interfaces, data classes, objects and sealed classes with examples.
Kotlin Classes
Declare classes, properties, constructors and init blocks.
8 tutorialsInheritance
Open classes, overriding, abstract classes and inheritance rules.
5 tutorialsInterfaces
Define and implement interfaces, functional interfaces and properties.
5 tutorialsData Classes
Data class declaration, copy, destructuring and equals/hashCode.
4 tutorialsObjects & Enums
Object declarations, companion objects, expressions and enum classes.
5 tutorialsSealed Classes
Sealed classes, when expressions and restricted type hierarchies.
4 tutorialsLearning track
Functional Kotlin
Lambdas, higher-order functions, scope functions, delegates and generics.
Lambda Expressions
Lambda syntax, parameters, return values and anonymous functions.
5 tutorialsHigher Order Functions
Functions as parameters, inline functions and return types.
5 tutorialsScope Functions
let, run, with, apply and also scope functions explained.
5 tutorialsDelegates
Property delegates, lazy, observable and class delegation.
5 tutorialsGenerics
Generic functions, classes, constraints, variance and star projection.
5 tutorialsExtension Functions
Add new behaviour to existing types with Kotlin extension functions and properties.
1 tutorialsLearning track
Standard Library
Lists, maps, sets, sequences, ranges, regex and file I/O in Kotlin.
List, Map & Set
Immutable and mutable collection operations, filtering and sorting.
6 tutorialsSequences
Lazy sequences, operations and when to use sequences vs lists.
5 tutorialsRanges
Range expressions, until, downTo and step in Kotlin.
4 tutorialsRegular Expressions
Regex matching, find, replace and common patterns in Kotlin.
5 tutorialsFile I/O
Read and write files, lines and path operations in Kotlin.
6 tutorialsLearning track
Kotlin Coroutines
Asynchronous programming with coroutines, dispatchers, async and Flow.
Coroutine Basics
Introduction, suspend functions, launch, runBlocking and coroutine scope.
6 tutorialsDispatchers
Main, IO, Default dispatchers and withContext for thread switching.
5 tutorialsAsync & Await
async builder, await, parallel work and exception handling.
5 tutorialsKotlin Flow
Cold flows, operators, StateFlow and SharedFlow basics.
6 tutorialsAdvanced Coroutines
Coroutine cancellation, channels and producer-consumer patterns.
2 tutorialsLearning track
JVM & Interop
Java interoperability, annotations and reflection on the JVM.
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