The **``setEncoding`` function** in Node.js alters the encoding of character data stored inside a readable stream. It comes as part of the ``stream`` module.

By changing character encodings, programmers can use the ``setEncoding`` method to interpret the same piece of data in multiple ways.

# Syntax
```
readable_stream.setEncoding(encoding)
```
# Parameters
The ``setEncoding`` function takes in only one parameter:
* **``encoding``**: a string that denotes the encoding in which the programmer wishes to interpret the data stored in a readable stream.
> If the programmer does not specify an encoding, it is not set to any default value.

Some of the most common character encoding(s) supported by Node.js are listed below.


# Return value
The ``setEncoding`` function returns a string that contains data read from a readable stream in the encoding specified by the programmer. If an encoding is not specified, a buffer is returned instead.

# Example
In the example below, we read data from two files using the ``createReadStream`` method and create two file objects. 

Subsequently, we use the ``setEncoding`` method to decode data from each stream using a different character encoding.

Using the ``console.log`` function, we output all the data elements of each stream onto the console and observe the output, since it depends on the encoding used to interpret it.





const file_stream = require('fs');
//creatomg two readable streams
const file1 = file_stream.createReadStream("file1.txt");
const file2 = file_stream.createReadStream("file2.txt");
//setting encoding of file 1 to hex
file1.setEncoding('hex');
//printing each data-element of file 1
file1.on('data', (data_element) => {
  console.log(data_element);
});
//setting encoding of file 2 to utf8
file2.setEncoding('utf8');
//printing each-data element of file 2
file2.on('data', (data_element) => {
  console.log(data_element);
});

  


> Note that both files contain identical data, but have completely different outputs.

What is the setEncoding function in Node.js?

The setEncoding function in Node.js changes the encoding of data in a readable stream, enabling interpretation in multiple encodings.