I was amazed to find out that the labels put on diagnostic tests can be rather misleading. For instance, I thought Comprehension measured a child's reading comprehension. Humm. I wonder where I could ever have gotten that idea. It actually measures among other things how well a child comprehends the world he lives in and social interactions. I am most grateful to "Bob" whom I met at the bulletin board at LDONLINE for the following definitions, put in parent friendly language. I had searched for 3 years for such understandable definitions, and with his help, I can now put this up for all of us to reference. If any diagnosticians out there have some additional input for lay persons to understand this web of diagnostics I would be most grateful. It is certainly a confusing area for parents in general.