I wrote some moths ago an article about the GC and highlighted some particularities (unsafe and unmanaged code, disposing and finalizing, etc).
When you are developing with .Net you will be sometimes faced to memory or resource leaks. Especially if you are using the BC.Net, since the BC.Net is using unsafe and unmanaged code. But even with X++ you will be more and more faced to such problems. So it is very useful to know as much as possible about causes, identification and resolving.