# Node.js and NPM
Node.js is an open-source, cross-platform, back-end, JavaScript runtime environment that executes JavaScript code outside a web browser. Node.js lets developers use JavaScript to write command line tools and for server-side scripting—running scripts server-side to produce dynamic web page content before the page is sent to the user's web browser. Consequently, Node.js represents a "JavaScript everywhere" paradigm, unifying web-application development around a single programming language, rather than different languages for server- and client-side scripts.
npm (for Node Package Manager) is a package manager for the JavaScript programming language. npm, Inc. is a subsidiary of GitHub. It is the default package manager for the JavaScript runtime environment Node.js. It consists of a command line client (called npm), and an online database of public and paid-for private packages (called npm registry). The registry is accessed via the client, and the available packages can be browsed and searched via the npm website.
This means that you can share and download any package that can facilitate others their work.
# Install Node.js
We will use Node.js to setup our back-end environment of our web projects. To install it download the correspondent version for your OS from here (opens new window). Installing node will also install npm as package manager.
# Install npm packages
# Windows Example
C:\>npm install <package>
# Mac OS Example
>npm install <package>