Understanding callbacks

Callbacks exploit JavaScript’s capability to pass functions. There are two essential parts to this technique:

• A function that is passed as an argument to another function
• The passed function is executed when a certain event happens

Let’s create a basic example to illustrate this concept. In the following code snippets, we will show how the callback is defined as an argument and how a function is passed as an argument when the execution occurs:

1. In this example, we will define a function (doSomething) that expects a function as an argument:

   const doSomething = (cb) => {
     console.log('Doing something...');
     cb();
   };

2. At this point, we have a function called doSomething that receives a function as an argument and executes it as the last step, this illustrates the idea that the callbacks are just a pattern where we expect that the next function to the executed is actually called as the final...