> For the complete documentation index, see [llms.txt](https://fundamentalslite.rocketacademy.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://fundamentalslite.rocketacademy.co/2-basic-data-manipulation/2.1-operations.md).

# 2.1: Operations

## Learning Objectives

* Use mathematical ***operators*** to perform mathematical ***operations*** in the console of the browser

## Introduction

{% embed url="<https://youtu.be/p24syWwKoO8>" %}

Coding means writing instructions for the computer to execute. We will begin with the most basic instructions the computer can execute, which is operations between 2 number values.

## **Setup**

1. Open a new tab in the Chrome browser by clicking File > New Tab, or pressing `Cmd+T` on Mac or `Ctrl+T` on Windows.
2. Open Chrome Developer Tools by clicking View > Developer > JavaScript Console, pressing `Cmd+Option+I` on Mac or `Ctrl+Shift+I` on Windows, or right-clicking anywhere in Chrome and clicking Inspect.
3. Select the `Console` tab in Chrome Dev Tools.

![Accessing the Developer tools in the Chrome browser setting](https://3179661644-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F4q5CU5JQTFABt9tKnZLj%2Fuploads%2FZos6gVRlGqCktku0fhB7%2FSSdevTools.png?alt=media\&token=5fc5a400-4b71-49c0-a48f-5290b719e9d7)

{% hint style="info" %}
You can use `Ctrl + L` or `Cmd + K` to clear your console
{% endhint %}

## Exercises

The JavaScript language is capable of performing math operations. Enter the following calculations into the Chrome Dev Tools Console, followed by the `Enter` key.

![Chrome console allows for in-browser calculations](https://3179661644-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F4q5CU5JQTFABt9tKnZLj%2Fuploads%2FwXYXiRI7sazb7nvXRQkx%2FSSdevToolsCalculate.png?alt=media\&token=9da4b521-1b15-44f0-ac56-d85c6a7adc93)

```javascript
2 + 2;
```

```javascript
4 * 2;
```

```javascript
4 / 2;
```

```javascript
4 - 2;
```

The input here is a mathematical equation typed in by the user, you. You have *instructed* the computer to perform a mathematical operation. The computer \_**returned** \_ an output, the evaluation of the equation.

{% hint style="info" %}
These exercises may seem trivial, but mathematical operations are at the core of all computing instructions. Computers fundamentally ***compute.*** That being said, they can get things predictably wrong. Try: `0.1 + 0.2` in your console. Did you get what you expect?

Coding Fundamentals will not cover why computers sometimes behave in odd ways, but you can read up more about this particular behaviour [here](https://0.30000000000000004.com) and [here](https://betterprogramming.pub/why-is-0-1-0-2-not-equal-to-0-3-in-most-programming-languages-99432310d476).
{% endhint %}

### Operators

In the above code, `+` `*` `-` and `/` are known as *operators.* Specifically, they are mathematical operators, as they perform a mathematical operation on 2 numbers. One other mathematical operator is the remainder operator, sometimes known as the modulus operator, defined with the `%` symbol. It returns the remainder after one number is divided by another; 10 `%` 3 will give us 1 because dividing 10 by 3 will result in a remainder of 1.

{% hint style="info" %}
This course will only involve basic math: adding and subtracting (usually by 1), dividing and multiplying, and comparing numbers.
{% endhint %}

We will soon see other kinds of programming operators and operations; in the next section, we will see the *assignment operator.*