Question

What is the difference between the events item:created vs item:added? When does each event get hit?

Answer 1

Looking at the code of the Sitecore.Data.Events.ItemAddedDelegate you may read that this delegate is deprecated and you should use ItemCreatedDelegate instead. From my tests:

1. Creating new item – both item:added and item:created are executed
2. Cloning item – both item:added and item:created are executed

3. Duplicating item – item:added is NOT executed, only item:created is executed

   namespace Sitecore.Data.Events
   {
       [Obsolete("Use the ItemCreatedDelegate event instead.")]
       public delegate void ItemAddedDelegate(object sender, ItemAddedEventArgs args);
   }
   

So in general, always use item:created