Node.js is a powerful JavaScript runtime environment that enables developers to execute JavaScript code on the server side. Built on Chrome's V8 JavaScript engine, it allows for asynchronous event-driven programming, which is essential for building scalable network applications. Unlike traditional web servers that handle requests in a blocking manner, Node.js employs a non-blocking I/O model, facilitating the handling of multiple connections simultaneously. This makes it an excellent choice for applications that require real-time data processing, such as chat applications and online gaming.

One of the standout features of Node.js is its rich ecosystem of modules and packages, facilitated by the npm (Node Package Manager). With npm, developers can easily install, share, and manage libraries that extend the functionality of their applications. This modular approach, combined with the JavaScript runtime environment's capabilities, empowers developers to create robust applications efficiently. To summarize, the key aspects of Node.js include:

1. Asynchronous event-driven architecture
2. High performance due to V8 engine
3. Vast module ecosystem via npm
4. Scalability for large applications

Node.js has gained immense popularity in backend development, and for good reason. Here are the top 5 advantages of using Node.js:

1. High Performance: Node.js is built on the V8 JavaScript engine, which compiles JavaScript directly to native machine code, resulting in faster execution. This performance boost makes it ideal for applications that require real-time data processing.
2. Scalability: Node.js uses an event-driven, non-blocking I/O model, allowing it to handle multiple requests simultaneously. This makes it easier to scale applications horizontally by adding more servers when traffic increases.

3. Rich Ecosystem: With a vast collection of libraries and frameworks available through npm (Node Package Manager), developers can easily integrate various tools and services. This rich ecosystem accelerates development and reduces time-to-market.
4. Full-Stack JavaScript: Using Node.js enables developers to use JavaScript for both frontend and backend development. This consistency simplifies the development process and improves collaboration among team members.
5. Strong Community Support: Node.js has a large and active community of developers who contribute to its growth. This means more resources, frequent updates, and extensive documentation are available to help developers overcome challenges.

Getting started with Node.js can be an exciting journey for beginners looking to dive into the world of server-side programming. First, you need to install Node.js on your machine. Head over to the official Node.js website and download the installer that corresponds to your operating system. After installing, you can verify the installation by opening your terminal or command prompt and typing node -v. This command will display the version of Node.js that you have installed, ensuring everything is set up correctly.

Once you have Node.js installed, it's time to create your first application. Start by creating a new directory for your project and navigate to it using the terminal. Then, initialize your project with npm init, which will prompt you to enter essential information about your application. After initializing, you can create a simple server using the built-in http module. Here’s a basic example:

const http = require('http');

const server = http.createServer((req, res) => {
    res.statusCode = 200;
    res.setHeader('Content-Type', 'text/plain');
    res.end('Hello World\n');
});

server.listen(3000, () => {
    console.log('Server running at http://localhost:3000/');
});

Run your server with node filename.js and visit http://localhost:3000 in your browser to see your first Node.js application in action!