Struct vs Class

I had the same question and found this article to be helpful:

https://learnappmaking.com/comparing-classes-vs-structs-swift/

In short, a struct creates a copy of data (it is a value type) while a class creates a reference to it (it is a reference type). This is the example used in the article:

"Reference Type: Bob has a phone number. He gives it to Alice. Alice doesn’t write down the phone number for herself, but instead remembers that Bob has it. When she needs the phone number, she asks Bob. When Alice accidentally changes one digit of the phone number, Bob’s phone number changes too. (You could picture this as Bob and Alice both holding the piece of paper the phone number is written on.)

Value Type: Bob has a phone number, and he gives it to Alice. Alice writes it down and now has her own copy. When she accidentally changes it, only her copy changes, and not the original phone number Bob has."

So it boils down to choosing the right one for the task, depending on whether it makes sense to copy data or make a reference to the original. The pros and cons of copies vs. references isn't entirely clear to me yet, but hopefully this helps answer your question somewhat.

The below link should assist you

https://developer.apple.com/library/content/documentation/Swift/Conceptual/Swift_Programming_Language/ClassesAndStructures.html#//apple_ref/doc/uid/TP40014097-CH13-ID82