Source: https://youtu.be/XTAziR-tY-A?si=QijLxZzW3AuipobM
Delegate and protocol is a pattern that is usually used in UI code.
It is a one-to-one communication pattern in Swift that allows one view to communicate with another view.
Example: bottom sheet and main view controller communication
Delegate (intern analogy), you don’t call delegate methods themelves, they get called automatically when they are told what to do.
Who gives the order?
Well, the one who knows the data, in this case, ProductSelectionVC (boss analogy).
So, the boss needs to give the command. They do this by calling a list of available commands to them, called Protocols. Which is basically a list of commands without their implementation. Protocols are like job description for the intern.