[NOTE: Run full screen, HD with Scaling off. It should display at 1280x720.]
A very short introduction to Generic Collections in Delphi 2009. Create a TList of Integers and show adding and removing items from it. Showing some of the differences in types, gotchas and errors you might get.
Generics, or parametrized types, are a type that works with another type that is defined later. Collections are a great example of using them. You create a generic TList, and then when you use it you declare what type it will contain. Then it will be strongly typed to that specific type, both in adding items and removing them.
Delphi Generics work with all types in Delphi: native types (Integer, string, etc.), Records, Objects and Interfaces.