Node.js is an excellent choice for building RESTful APIs due to its non-blocking I/O, which allows handling multiple requests simultaneously, making it efficient and fast for API interactions.

Node.js has become a popular framework for developing RESTful APIs because of its unique architecture and capabilities. Let's delve deeper into why Node.js is a great choice for building RESTful APIs.

1. Non-blocking I/O Model: At the core of Node.js is its event-driven, non-blocking I/O model. This means that operations such as reading files or querying databases do not block the execution of other operations. Instead, Node.js can handle multiple requests at once, which is essential for API performance. When a request is made to a RESTful API, Node.js can continue processing other requests without waiting for the previous one to finish, making it ideal for high-traffic applications.

2. Single-threaded Event Loop: Node.js utilizes a single-threaded event loop to manage connections. This design allows it to efficiently handle thousands of simultaneous connections without the overhead associated with thread management. Traditional server architectures may create a new thread for each request, which can lead to memory exhaustion under high loads. In contrast, Node.js remains lightweight and performs efficiently, making it suitable for RESTful services that expect varying levels of traffic.

3. Fast Execution: Node.js is built on Chrome's V8 JavaScript engine, which compiles JavaScript into machine code. This results in fast execution times for JavaScript code, enabling APIs to respond quickly to requests. The speed of execution is particularly beneficial for real-time applications that require rapid data processing and response.

4. JSON as a Native Data Format: Since APIs often rely on JSON as the data interchange format, Node.js naturally fits this requirement. Being a JavaScript runtime, it can parse JSON data effortlessly, simplifying the process of sending and receiving data in APIs. This native support for JSON enables smoother data handling, reducing the complexity of data transformations between client and server.

5. Robust Ecosystem and Libraries: Node.js has a rich ecosystem with a plethora of libraries and frameworks available through npm (Node Package Manager). Developers can easily integrate various functionalities into their APIs, such as authentication, validation, and data access. Popular frameworks like Express.js further streamline the process of creating RESTful APIs by providing built-in methods for routing and middleware management, enhancing development efficiency.

6. Scalability: As applications grow, so does the need for scalability. Node.js allows for horizontal scaling, meaning that developers can deploy multiple instances of their application across different servers to handle increased traffic. This scalability ensures that RESTful APIs can serve a larger number of concurrent users without degradation in performance.

7. Real-time Data Processing: Node.js excels in applications that require real-time data processing, such as chat applications or collaborative tools. By implementing WebSockets in conjunction with RESTful APIs, developers can create seamless real-time interactions, enhancing the user experience. This capability is increasingly important in modern applications that demand immediate feedback and updates.

8. Cross-Platform Development: Node.js can run on various operating systems, including Windows, macOS, and Linux. This cross-platform capability means that developers can build RESTful APIs that can be deployed in different environments without significant modifications. It also allows for consistent development practices across teams working on different platforms.

9. Community Support and Resources: The Node.js community is large and active, providing a wealth of resources, tutorials, and forums for support. Developers can easily find solutions to common problems, share knowledge, and collaborate on projects. This community-driven support system is invaluable for building and maintaining RESTful APIs.

10. Security Features: While building RESTful APIs, security is paramount. Node.js offers various security features, such as built-in protection against Cross-Site Request Forgery (CSRF) and easy implementation of HTTPS. Developers can use various libraries to enhance security further, ensuring that their APIs are protected against common vulnerabilities.

In summary, Node.js's non-blocking I/O model, single-threaded architecture, speed, and native support for JSON make it an excellent choice for developing RESTful APIs. With a robust ecosystem and community support, Node.js provides the tools and resources necessary to build scalable, efficient, and secure APIs.