Callback Hell / Pyramid of Doom

If you did something like that, in order to solve the previous exercise you are right. Congrats! However you also understand that this code is very hard to maintain and to debug. We have only 5 nested callbacks and it is already very hard to identify what is inside what. Where something begins, and most importantly, where does it end. 

This situation is called callback hell, or pyramid of doom. Is the pattern when the code we write spreads more horizontally than vertically (similarly to putting multiple nested if statements one inside the other). 

Well thankfully there is a way to perform exactly the same thing but in a syntactically more straightforward and easier to debug way. The promises!