Use Case 1: Node.js in Server Operations

When you execute a Java command on a Java file, it runs within the Java runtime environment. Similarly, accessing a PHP file through a browser involves an Apache server that calls upon the PHP runtime to execute the script. Node.js functions in the same way, allowing for the execution of JavaScript files.

Like other runtime environments, Node.js comes equipped with built-in commands that you can use in your JavaScript files to interact with local files, databases, and processes. This means you can set up a server using Node.js that executes JavaScript files in response to user requests.

In this instance, Node.js operates as a component of the server, akin to a Java-based server or Apache with PHP. The JavaScript files reside on the server and are not downloaded by the browser; rather, they are executed internally on the server by Node.js. The outcome is then sent to the user. For instance, in PHP, you might use echo "hello" to send a response, whereas in JavaScript with Node.js, you would employ console.log("hello") to achieve the same result. This means "hello" is sent back to the user who requested the resource.

Use Case 2: Node.js in Development Environments

Now that you understand the first use case of Node.js as a server-side runtime for JavaScript, let’s delve into the second, which is entirely distinct from the first. Although both utilize Node.js, they represent two separate applications of it.

One instance of Node.js runs on the server to execute JavaScript and serve data to users. In contrast, another instance resides on your local machine, serving a different purpose entirely. This local instance is not meant to serve files; instead, it functions as part of your development environment.

This concept can be somewhat perplexing if you're accustomed to languages like Java, PHP, or standard JavaScript. You might wonder why Node.js is necessary on your local computer.

The rationale is that developers sought to create various tools that could streamline different development tasks. For example, tools like ESLint help identify errors in JavaScript code and ensure adherence to coding standards. Such tools need to process all files in a project and provide results, essentially acting as applications themselves.

Consequently, it was envisioned that these applications could be developed using JavaScript, necessitating the presence of a runtime environment on the local machine. Currently, Node.js is the most popular runtime for such tasks.

In summary, Node.js serves two distinct purposes: one for server-side processing of JavaScript backend files that deliver responses to users, and another for executing development applications. These are entirely separate instances of Node.js, with no connection to the browser or the end-user.

The first video titled "10 Things I Wish I Knew Before I Started Programming" provides valuable insights for beginners looking to navigate the programming landscape.

The second video, "Things I Wish I Knew Before Becoming A Software Developer," shares essential tips and experiences from seasoned developers.