FileSystem APIs

In the previous section, we learned about the global variables available to us in the Node.js execution context. In this section, we will learn about the FileSystem APIs, which are the APIs that are used to access files and directories, read and write data to files, and much more.

But before we dig into the FileSystem APIs, we need to understand streams. In Node.js, a Stream is an abstract interface that represents streaming data. In the previous section, we used the standard I/O and briefly mentioned that they are streams, so let's understand them in detail.

Streams can be readable, writable, or both. They are event emitters, which means that to receive data, you need to register event listeners, just like we did with standard input in the previous section:

process.stdin.addListener('data', (data) => {
  ...
});

In the next section, we will continue to build on our understanding of the previous sections and see that streams are...