Data Types & Variables

Learn about variables and the various data types that are supported in Kotlin.

Key Concepts

Review core concepts you need to learn to master this subject

Mutable Variables

Immutable Variables

Type Inference

String Concatenation

String Templates

Built-in Properties and Functions

Character Escape Sequences

Arithmetic Operators

var age = 25
age = 26

A mutable variable is declared with the var keyword and represents a value that is expected to change throughout a program.

Data Types & Variables

Lesson 1 of 3

1
Introduction
In this lesson, we’ll explore the building blocks of a programming language - data types and variables. A data type represents the type of value an object possesses. Here are a few of the types o…
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2
Declaring a Mutable Variable
Now that we’ve familiarized ourselves with the concept of variables, let’s learn how to create a variable in Kotlin. A complete variable declaration and initialization resembles the following form:…
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3
Declaring an Immutable Variable
Another type of variable that exists in Kotlin is the immutable variable. The term, immutable, signifies a variable whose value cannot mutate or change after its initialization. _Immutable variab…
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4
Type Inference
In Kotlin, we can save keystrokes and optimize our variable declarations with a feature known as type inference. Type inference indicates that the compiler can infer the type of a declared vari…
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5
Review
Excellent job! You’ve completed the first lesson of the Data Types & Variables section. Let’s review what was covered. - A variable declaration consists of a val or var keyword followed by a name…
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