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👶  Children (ELI5)

Hello, young adventurers! Are you ready to explore the magical world of programming languages? Today, we're going to dive into the swanky and exciting Kotlin language. Kotlin is like a treasure chest filled with amazing features and fun surprises. So come on, let's get started!

Once Upon a Time in a Land Called JetBrains... 🏰

Our story begins at JetBrains, a company filled with brilliant minds who were on a quest to create a better programming language. They wanted something powerful like a dragon , yet elegant like a swan . And so, in 2010, they crafted Kotlin, named after the Kotlin Island near St. Petersburg, Russia!

As time passed by, more and more people became excited about Kotlin's superpowers. In 2017, Google joined the fan club and made Kotlin an official language for Android development. This helped Kotlin rise to fame and be adored far and wide.

Magic Spells or, umm, Features! 💫

Kotlin is like your handy spellbook , containing lots of nifty features that make coding fun and enjoyable. Here are some magical features that set Kotlin apart:

  1. Interoperability with Java: Kotlin can happily coexist with Java code in the same project! It's like having two best friends who play together nicely.
  2. Conciseness: Kotlin helps you write less code without losing any clarity or functionality. Imagine having magic words that do the work of long spells.
  3. Safer Code: With its unique way of handling nullability, Kotlin helps prevent "NullPointerExceptions" or NPEs. It's like having a shield to protect you from sneaky bugs!
  4. Extension Functions: Kotlin allows you to add new functions to existing classes, even if you don't have access to their source code. It's like adding new tricks to your favorite toy without opening it up!

Your First Kotlin Adventure 🌟

Ready for your first taste of Kotlin magic? Let's create a simple program that prints "Hello, Kotlin!" to the console. Here's the code you need:

fun main() {
    println("Hello, Kotlin!")

Did you notice the fun keyword? It's short for "function," and it's how we define new functions in Kotlin. The main function is like the starting point of a treasure hunt: it's where our adventure begins!

When we run this program, it will print:

Hello, Kotlin!

The Magic of Variables 🔮

In Kotlin, we can store information using variables. Think of variables as little treasure chests that hold different types of data. Here's an example:

val name = "Ada"
val age = 9

In this example, we use the val keyword to create two variables: name and age. name stores a text called a String, and age stores a number called an Int. Notice how we don't have to tell Kotlin what type of data each variable holds? Kotlin is smart and can figure it out!

Now let's use our newly created variables to print a message:

fun main() {
    val name = "Ada"
    val age = 9
    println("Hello, my name is $name, and I am $age years old!")

When we run this program, it will print:

Hello, my name is Ada, and I am 9 years old!

See those $ signs? They allow us to embed our variables directly into the text. It's like having a magic key to open our treasure chests and reveal their contents.

Building Castles 🏰 (Or, You Know, Functions)

Functions in Kotlin are like magical blueprints that tell your program how to perform specific tasks. We've already seen the main function, but we can create our very own custom functions too! Let's create a function to find the treasure:

fun findTreasure() {
    println("You found a treasure chest filled with gold coins!")

fun main() {

Our findTreasure function has one job: to print a message about finding treasure. In our main function, we "call" our findTreasure function by using its name followed by a pair of parentheses (). When we run this program, it will print:

You found a treasure chest filled with gold coins!

Congratulations, you found the treasure!

The Wonders of Kotlin Continue! ✨

We've only scratched the surface of the Kotlin realm. There are so many more enchanting things to discover, like:

  • Control Flow: Direct your code's path with if, when, and loops.
  • Classes and Objects: Define and create your own magical creatures or fantastic heroes .
  • Collections: Organize and control vast arrays of data like a powerful sorcerer.

Your Kotlin adventure has just begun, young explorer! With every step you take, you will uncover more thrilling secrets and unleash your creativity. So forge ahead and let Kotlin's magic guide you! is a collection of articles on a variety of technology and programming articles assembled by James Padolsey. Enjoy! And please share! And if you feel like you can donate here so I can create more free content for you.