Asynchronous I/O

I’m learning about asynchronous I/O in the Node.js chapter of Eloquent JavaScript. I/O is input output. One way of handling I/O is reading and returning files once they are fully read (synchronous). This may cause a program to freeze up while it is still waiting for information.

An asynchronous interface allows scripts to continue running while it does other work and call a function (callback) after it is done.