Introduction to JavaScript

Introduction to JavaScript

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1. Basic Concepts

Our first section will introduce you to JavaScript and explore its syntax. This initial step will give you a fundamental understanding of JavaScript's syntax, setting the stage for more in-depth learning in subsequent sections.

About JavaScript

Challenge: Console Output

Challenge: Single-line Comment

Challenge: Multi-line Comment

2. Variables and Data Types

We'll dive into the essential data types that JavaScript operates with. We'll begin by distinguishing between literals and variables and then explore the diverse range of data types used in JavaScript. This knowledge will form a solid foundation for your journey into JavaScript.

Challenge: Defining the Variable

Data Types Overview

Challenge: Array Operations

3. Basic Operations

We're acquainted with the various data types. It's time to roll up our sleeves and learn how to manipulate them. In this third section, we'll explore the operations that can be performed with each data type, equipping you with practical skills to work effectively with JavaScript's data structures.

Mathematical Operations

Operations with Assignment

Increment and Decrement

Challenge: Variable Operations

Comparison Operations

Logical Operations

Challenge: Comparing Variables

String Concatenation

Challenge: Sentence Building

4. Conditional Statements

Delve into the art of controlling the flow of execution in JavaScript. It's a powerful skill that enables us to instruct the interpreter precisely on how to behave under various conditions. You'll gain the ability to orchestrate your code's behavior.

Challenge: Determining Size

5. Loops

Uncover the code optimization through the use of loops. Loops allow us to streamline our code by performing repetitive actions efficiently. We'll delve into JavaScript's different types of loops and discover how to wield their power effectively.

Challenge: Printing Numbers from 5 to 9

Challenge: Tigers

Challenge: Stopping and Skipping

6. Functions

Unlock the potential of functions as essential tools for crafting simple yet powerful programs. You'll master creating and utilizing functions, empowering you to simplify your coding endeavors and enhance your problem-solving skills.

What is a Function?

Challenge: My Name

Conteúdo do Curso

Introduction to JavaScript

Introduction to JavaScript

Array

The array is the most useful data structure.

Note
A data structure is a specialized format for organizing and working with data collection. An array is a collection of items where each item is a value.

Creating an Array

To create an array, use square brackets []:

This creates an empty array with no elements. To create an array with elements, place the elements inside [] and separate them with commas (,):

Note
The last element in the array should not have a comma after it.

To print an array, simply use console.log():


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const arr = [1, 2, 3, 4, 5];

console.log(arr);

Indexes

Each element in an array has a unique index.

Note
Indexes start from 0. The first element has an index of 0, the second element has an index of 1, and so on.

Accessing array data is done by specifying the index in square brackets ([index]) after the array name:


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const arr = [1, 2, 3, 4, 5];

const thirdElement = arr[2];  // retrieving the 3rd element

console.log(thirdElement);

Arrays can hold different data types, including number, string, boolean, and more.


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const arr = [2441.23, "Hello!", false];

console.log(arr[0]);
console.log(arr[1]);
console.log(arr[2]);

Length Property

The length property is a built-in property of arrays that represents the number of elements in that array. To use this property, use the following syntax:


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const arr1 = [10, 20, 30];
const arr2 = [15, 25, 35, 45, 55];

const x = arr1.length; // `x` variable represents the `arr1` length
const y = arr2.length; // `y` variable represents the `arr2` length

console.log(x);
console.log(y);

Tudo estava claro?

Seção 2. Capítulo 6

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