How process.nextTick() works in Node.js?
The process object is a one of the few global objects provided by the Node.js core API. It can be access from anywhere, thus its methods can also be accessed. Such is a method called process.nextTick() which is used by developers in realtime applications everyday to defer the execution of a function until the next Event Loop Iteration.
In Node.js, each iteration of an Event Loop is called a tick. To schedule a callback function to be invoked in the next iteration of the Event Loop, we use process.nextTick(). It just takes a callback with no time bound, since it will be executing in the next iteration of the Event Loop.
console.log('Processed in next iteration');
console.log('Processed in the first iteration');
The above snippet is an example of how process.nextTick() works. You can save the snippet in a file.js and run using $node file.js from your terminal. You will definitely notice that the second console.log printed before the console.log associated with function cb().
Processed in the first iteration
Processed in next iteration