Node.js has revolutionized the way developers approach server-side programming by allowing them to use JavaScript, a language traditionally reserved for client-side development. This unification simplifies the development process, enabling developers to use the same language across both the frontend and backend of their applications. As a result, teams can streamline their workflows, reduce the learning curve for new developers, and enhance collaboration. Moreover, the asynchronous, non-blocking architecture of Node.js allows for high performance and scalability, making it an ideal choice for applications that require real-time data processing.

One of the key features of Node.js is its event-driven, non-blocking I/O model that supports thousands of concurrent connections with minimal overhead. This architecture is perfect for handling activities like real-time messaging and streaming data, making it well suited for applications such as chat apps and live updates. Furthermore, by leveraging the vast ecosystem of open-source libraries available through npm (Node Package Manager), developers can quickly access a wealth of resources that enhance functionality and reduce development time. In summary, the synergy between JavaScript and Node.js provides an efficient platform for robust server-side applications.

Node.js has revolutionized the way developers build server-side applications. Among its many strengths are the plethora of libraries that help streamline development processes. Here are the top 10 Node.js libraries every developer should know:

1. Express.js - A minimal and flexible Node.js web application framework providing a robust set of features for web and mobile applications.
2. Mongoose - A MongoDB object modeling tool designed to work in an asynchronous environment.
3. Socket.io - Enables real-time, bidirectional communication between web clients and servers.
4. Async - A utility module that provides straight-forward, powerful functions for working with asynchronous JavaScript.
5. Jest - A delightful JavaScript testing framework particularly useful for testing Node.js applications.
6. Passport - An authentication middleware for Node.js, extremely flexible and modular.
7. Body-parser - A Node.js body parsing middleware for handling JSON, buffers, and URL-encoded data.
8. Lodash - A modern utility library delivering modularity, performance, and extras.
9. Cheerio - Fast, flexible, and lean implementation of core jQuery designed specifically for the server.
10. Node-fetch - A light-weight module that brings `window.fetch` to Node.js.

Building your first API with Node.js can seem daunting, but it's a rewarding experience that opens up numerous opportunities in web development. To start, you'll need to set up your environment by installing Node.js and a package manager like NPM. Once installed, create a new project directory and initialize it using the command npm init -y. This command will create a package.json file where you can manage your project’s dependencies. Next, install the Express framework by running npm install express, which will simplify the process of creating your server.

Now that your environment is ready, it's time to start coding your API. Begin by creating a new file, for example, app.js. In this file, require the Express module and create a basic server using the following code:

const express = require('express');
const app = express();
const PORT = process.env.PORT || 3000;

app.get('/api', (req, res) => {
  res.send('Hello World! This is my first API!');
});

app.listen(PORT, () => {
  console.log(`Server is running on http://localhost:${PORT}`);
});

Finally, run your server with node app.js and visit http://localhost:3000/api in your browser to see your first API response!