The node.js performs the streams and file system operations for interacting with operating system or other run time processed and uses buffer objects to represent the binary data in the form of a sequence of bytes.
The node.js buffer size allocation is provided at the creation of the instance and has fixed-size blocks of memory which cannot be changed.
node.js buffer examples
// creates zero-filled Buffer of length 10.
const zeroFilledBuffer = Buffer.alloc(10);
// Creates a Buffer containing the bytes [4,5,6].
const containsBytes = Buffer.from([4, 5,6]);