Types in Depth

Types in Depth

In this lesson — part of Data Deep Dive — you'll learn types in depth in Kotlin and why it matters in real work.

Why it matters

Types tell you what operations make sense and catch whole classes of bugs early.

Key ideas

• Common types: text, numbers, booleans
• Type conversion and coercion
• When to be explicit about types
• Type errors and how to read them

In practice

Here's how it looks in idiomatic Kotlin:

fun main() {
    val n: Int = 42
    val price: Double = 9.99
    val active: Boolean = true
    val asLong: Long = n.toLong()   // explicit conversion required
    println("$n $price $active $asLong")
}

Kotlin note: Kotlin has no implicit numeric widening — you must call explicit toX() converters like toLong() or toDouble().

Try it yourself

Exercise: In Kotlin, convert a number to text and back, and print both.

Recap

You now understand types in depth and can apply it in Kotlin. Mark this lesson complete and continue to the next one.