Kurssisisältö

Introduction to JavaScript

1. JavaScript Fundamentals

About JavaScript Understanding JavaScript Syntax Challenge: Console Output in JavaScript Using Comments to Document Code Challenge: Write a Single-Line Comment Challenge: Write a Multi-Line Comment

2. Variables and Data Types in JavaScript

Understanding Variables in JavaScript Challenge: Define the Variable Using const for Constants Exploring JavaScript Data Types Working with null in JavaScript Introduction to Arrays Array Methods and Manipulation Challenge: Perform Array Operations

3. Performing Operations in JavaScript

Understanding Assignment Operators Mathematical Operations in JavaScript Assignment Operators in JavaScript Increment and Decrement Operators Challenge: Variable Operations Practice Comparison Operators in JavaScript Logical Operators Explained Challenge: Compare Variables in JavaScript Concatenating Strings in JavaScript Challenge: Build Sentences with JavaScript

4. Controlling Program Flow with Conditional Statements

Mastering if Statements in JavaScript Using else for Alternative Outcomes Applying else if for Multiple Conditions Challenge: Determine Sizes with Conditionals

5. Looping Through Data in JavaScript

Understanding the while Loop in JavaScript Using the do while Loop for Iteration Challenge: Print Numbers from 5 to 9 Mastering the for Loop in JavaScript Challenge: Console Tigers with Loops Breaking Out of Loops with break Skipping Iterations with continue Challenge: Stop and Skip in Loops

6. Functions in JavaScript

What Are Functions in JavaScript?Defining Functions in JavaScript Challenge: Write a Function – My Name Using Function Arguments Effectively Returning Values from Functions Challenge: Create a Sum Function Course Summary & Next Steps

Understanding JavaScript Syntax

JavaScript follows a default syntax with parentheses, curly brackets, and semicolons.

Let's create a simple program and delve into its syntax. In JavaScript, you don't need to define a main function as required in languages like C, C++, Java, GoLang, etc. You can directly write your code:


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console.log("Hello, user!");

In the example above, we've crafted a program that uses the console.log() method to print Hello, user! to the console.

Now, let's break down the syntax:

To begin, we employ the console.log() method. This method serves the purpose of printing values in the console;
Following that, we place "Hello, user!" within this method, enclosed in parentheses ();
The quotes (" or ') serve as indicators to JavaScript, signifying that Hello, user! is plain text and not a function or any other program-related keyword;
Lastly, the semicolon (;) functions as the command terminator, marking the conclusion of a command.

A program comprises a series of commands. If you intend to print text multiple times, you can utilize the semicolon ; to signal the end of each command:


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console.log("Command 1");
console.log("Command 2");
console.log("Command 3");

In the example above, the semicolon ; serves as the separator for the three commands in our code:

The first command is console.log("Command 1") followed by ; (indicating the end of this command);
Subsequent commands are structured similarly.

1. What is the purpose of the `console.log()` method?

2. Why do we use quotes (" or ') around text like "Hello, user!"?

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Introduction to JavaScript

Understanding JavaScript Syntax

1. What is the purpose of the console.log() method?

2. Why do we use quotes (" or ') around text like "Hello, user!"?

1. What is the purpose of the `console.log()` method?