Gain insights into Node.js fundamentals, event loops, and multithreading. Delve into file systems, global objects, and advanced modules. Discover how to create a food delivery web application.

final.tar.gz

TCP_job

HTTP_test

Project_3

Project_1

Project_2

Project_0

timer_demo

UDP_job

Project_demo

sayMyName

logger

nodemon app

npm terminal

UDP_chat_nodemon

TCP_chat_nodemon

run-app.js

terminal-app.js

Node.js is an open-source, cross-platform, JavaScript runtime environment that executes JavaScript code outside of a web browser. This course is your guide for learning the fundamentals of Node.js.

In this course, you'll start by understanding the inner workings of Node.js. More specifically, you’ll explore its features, how event loops work, and how multithreading works. You’ll then move on to the fundamentals of Node.js like file systems, global objects, and the Buffer class.

In the latter half of the course, you’ll explore more advanced concepts like modules,  events,  and packages. At the end of this course, you will get hands-on with Node.js and create your own food delivery web application.

By the end of this course, you will have a new, in-demand skill to put on your resume and a cool project to add to your portfolio.

Learn Node.js: The Complete Course for Beginners

# What is package.json?
Every published package has a `package.json` file. This file makes it easy for others to manage and install the package. It gives information to npm that allows it to identify the package as well as handle the package's dependencies. Node.js is only aware of two fields: `name` and `version`. However, other fields, such as `dependencies`, and `main` are vital for a package to be used.

Let's take a look at the content in the `package.json` of **[jsonwebtoken](https://www.npmjs.com/package/jsonwebtoken)**, a popular Node.js package that is used for authentication.

JSON Web Token implementation (symmetric and asymmetric)

jsonwebtoken

There are several different descriptors in the `package.json` file, let's take a look at some of the common ones.
| **Field** | **Explanation** |
|-|-|
| `name` | The name of the package |
| `version` | Package version in major.minor.patch format |
| `description` | A few words to describe the package |
| `main` | The entry point of the package, used when `require("package name")` is run; it is resolved to `require(package.json:main)` |
| `repository` | URL of the repository |
| `keywords` | Used to describe the package and improve search results |
| `dependencies` | List of dependencies that are available on npm |
| `devDependencies` | Recommended or required dependencies to modify the package |
Other fields such as -— `author`, `contributors`, and `homepage` -- are used to give credit and links for additional references.


# Package dependencies 
Dependencies can be added to the `package.json` file automatically, using the CLI.
## `dependencies`
To add dependencies to the package.json file from the command line, you can install them in the root directory of the package. This is the command:
```
npm install <package-name>
```
## `devDependencies`
For devDependencies we use the `--save-dev` flag. This is the command:
```
npm install <package-name> --save-dev
```

> We can also edit the `package.json` file manually to add dependencies using a text editor.

# Installing dependencies 
While working on a Node.js project, we often install a number of packages and dependencies. Another benefit of the `package.json` file is that it allows us to install all the dependencies with just a single line. The `package.json` is located in the root directory of projects and contains all the dependencies of the project. So, to install the dependencies for a project, all you have to do is go to the root directory of the project and use the following command:
``` 
npm install
```
This command is very useful when installing projects from websites such as GitHub.

Let's try to install the dependencies for [this](https://github.com/jmsv/simple-mern) GitHub project. We have already downloaded the project for you using the `git clone` command. Just try to install it.
> Don't forget to go into the project directory before running the install command. You can view all the contents of the current directory using the `ls` command. You can go to a directory by using the command `cd directory-name`.

This project consists of two components: the server-side and the client-side. The root directory contains a `package.json` file for the server. However, if you navigate into the `client` folder, you will find another `package.json` file. This file contains the dependencies for the client component. These dependencies can be installed by running `npm install` in the client folder.




Learn about the importance of the package.json file.

Introduction

Fundamentals

Advanced Topics

Packages

Project

Appendix

package.json

What is package.json?