NodeJs
What is NodeJs?
Node.js is an open-source, cross-platform, JavaScript runtime environment that executes JavaScript code outside a web browser.
Installation
First download the latest version of NodeJs from here.
We recommend to use the LTS version (for Long Term Support).
Usage
Hello World
// let's create a file called hello.js
console.log("Hello World!");
Run the file
# open a terminal and run the following command
node hello.js
# you should see the following output
> Hello World!
Dependencies
NodeJs comes with a package manager called npm (Node Package Manager).
You can install dependencies using the following command:
# install a package locally
npm install <package-name>
# install a package globally
npm install -g <package-name>
Package.json
The package.json file is used to store metadata about your project.
You can create a package.json file using the following command:
npm init
This will create a package.json file in the current directory with the following content
{
"name": "my-project", -> the name of your project
"version": "1.0.0",
"description": "My Project Description",
"main": "index.js", -> the entry point of your project
"scripts": { -> scripts to run
"test": "echo \"Error: no test specified\" && exit 1"
},
"dependencies": { -> dependency list
"dependency-name": "^1.0.0",
"other-dependency-name": "^1.0.0"
},
"author": "Your Name",
"license": "ISC"
}
Full Documentation
You can find the official documentation here.