What is ‘Callback’ in node.js?

Question

Am new to node.js.In every document i saw node js is nothing but non blocking and event driven.But am still unaware about what is non-blocking & event driven.Can any one please explain about this.

Answer 1

Node.js, being an asynchronous platform, doesn't wait around for things like file I/O to finish - Node.js uses callbacks. A callback is a function called at the completion of a given task; this prevents any blocking, and allows other code to be run in the meantime.