Variable values are often manipulated using various operators and functions. Below are some commonly used operators and functions:

Used for mathematical calculations such as addition and subtraction, multiplication and division. For example, you can calculate the sum of two variables as follows:

This calculates the sum of variables "x" and "y" and stores the result in a new variable named "sum".

Used to compare two variables and give a true or false value depending on whether they are equal or smaller. For example, you can compare two variables as follows:

This compares whether the variable "x" is smaller than the variable "y", and stores the result in a new variable called "comparison".

You can combine two strings using the plus operator. For example, you can combine two strings as follows:

This connects two strings ("Matti" and "Meikäläinen") and adds a space between them. The result is saved in a new variable named "nimi".

Here is an example of JavaScript code that uses various operators:

Variable values are often manipulated using various operators and functions. Below are some commonly used operators and functions:

## **Arithmetic operators**

Used for mathematical calculations such as addition and subtraction, multiplication and division. For example, you can calculate the sum of two variables as follows:

```javascript
var x = 5;
var y = 10;
var sum = x + y;
```

This calculates the sum of variables "x" and "y" and stores the result in a new variable named "sum".

---

## 
Comparison operators

Used to compare two variables and give a true or false value depending on whether they are equal or smaller. For example, you can compare two variables as follows:

```javascript
var x = 5;
var y = 10;
var comparison = x < y;
```

This compares whether the variable "x" is smaller than the variable "y", and stores the result in a new variable called "comparison".

---

## 
String Concatenation

You can combine two strings using the plus operator. For example, you can combine two strings as follows:

```javascript
var firstname = "Matt";
var lastname = "Meikäläinen";
var name = firstname + " " + lastname;
```

This connects two strings ("Matti" and "Meikäläinen") and adds a space between them. The result is saved in a new variable named "nimi".

---

## Example

Here is an example of JavaScript code that uses various operators:

---

## Practice

@embed ef77093038c0


JavaScript Operators

This course is an introduction to web development and focuses on the basics of HTML, CSS, JavaScript and backend systems. The aim of the course is to provide students with the necessary skills and knowledge to design, develop and understand simple web applications.

This course is an introduction to web development and focuses on the basics of building websites, namely HTML, CSS, JavaScript, and fundamentals of backend systems. The goal of the course is to provide you with the necessary skills and knowledge to design and develop simple full-stack web applications, as well as understand web applications made by others.

In the first part, HTML is studied, which is a markup language used in building websites.


The second part covers the basics of CSS, such as the use of style sheets, rules, selectors, and formatting. It also covers advanced features of CSS, such as animations and responsive design.

In the third part, we will study JavaScript, which is currently an incredibly important tool in both frontend and backend development, and thus also in cybersecurity and ethical hacking.

In the final part, we will learn how to build back-end systems using the Python Flask framework. You will learn the basics of back-end systems, such as using databases, authentication, session management, and access control.

You can do the course exercises on your own computer if you want, but each code example has a button that allows you to directly run the code in the browser and see what the page looks like or what the script prints. So you do not need to install anything, but you can if you want.

It is recommended but optional to create an account on replit.com service. In that case, you can just click "Fork" on the code examples to make a copy for yourself to play with

JavaScript Operators

Arithmetic operators

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