<aside> 💡 The internet has thousands of already implemented JavaScript code for tons of use cases. These are named libraries / dependencies.

</aside>

Each JavaScript application has a package.json file where these libraries / dependencies are put. This is done for the sake of sharing the code with others.

How to initialize a JavaScript application?

Run the following command in your desired directory:

npm init

This will generate a basic package.json file for you. For example:

{
  "name": "workshop3",
  "version": "1.0.0",
  "description": "This is for a showcase of how npm works.",
  "main": "index.js",
  "scripts": {
    "test": "echo \\"Error: no test specified\\" && exit 1"
  },
  "author": "Damian",
  "license": "MIT"
}

How to install libraries?

In order to install a library, you run the following command:

npm install <library-name>

# For example:
npm install convert

After that, you’ll see the package.json file updated with the new dependency:

{
  "name": "workshop3",
  "version": "1.0.0",
  "description": "This is for a showcase of how npm works.",
  "main": "index.js",
  "scripts": {
    "test": "echo \\"Error: no test specified\\" && exit 1"
  },
  "author": "Damian",
  "license": "MIT",
  "dependencies": {
    "convert": "^4.13.2"
  }
}

Now, if you share the apps code with others, they will install the same version of convert library as it is described in package.json.

Got the code from a colleague, how do I install the dependencies?

In order to install all the dependencies the first time you clone the code, you run:

npm install

This will install all the dependencies from package.json with their respective versions.