Today we're talking about state machines and sequences - capturing what a product does vs. what a product is. This is one of the things that a lot of people ether don't think about or think about in a vague way. What the product does impacts what it needs to be - this is yet another aspect of the product. We talked about the flow diagram, the heirarchical list of what it is - so now this is how you separate what it does from what it is - which requires  skill. The experience of the product is everything together - it is very useful to be able to think about aspects of the product as distinctions - you use all of the noun pieces/features in the product and what it does is the verb. You constrain your vocabulary by what "is" the product. We get into the semantics of "product" and product concepts to be precise about the product description, especially at the beginning.  Eventually the code is a very specific sequence of events.