What types of streams are there in Node.js?

In Node.js, there are four main types of streams that implement the EventEmitter interface and allow working with data streams:

1. Readable — streams from which data can be read (e.g., reading a file, HTTP request).
2. Writable — streams to which data can be written (e.g., writing to a file, sending an HTTP response).
3. Duplex — streams that are both readable and writable (e.g., TCP sockets).
4. Transform — a special type of duplex stream that can modify or transform data as it passes through (e.g., compression, encryption).

Example of using readable and writable streams:

const fs = require('fs');

const readable = fs.createReadStream('input.txt');
const writable = fs.createWriteStream('output.txt');

// Copy file contents
readable.pipe(writable);

Thus, streams enable efficient handling of large amounts of data without loading all information into memory at once.