What is the event loop in JavaScript?

Event Loop

The event loop has one simple job which is to monitor the Call Stack and the Callback Queue. If the Call Stack is empty, it will take the first event from the Callback Queue and will push it to the Call Stack.

Such an iteration is called a tick in the Event loop.

The event loop says I am gonna check before every single line of code run, is the call stack empty? Is there something in the queue?. If the call stack is not empty, if there is still further global code to run, then I will not even go look at the queue. But, if the call stack is empty I will go to the queue, I will grab the function from there and I will put it on the call stack.