I'll let you know when I'm through. Seriously, what is said today is important in the sense that it establishes a context for what we will study for the rest of the semester. Please don't sleep. If you must sleep, turn on your recorder for study later this evening. There could be a quiz.
Phonology is the study of the discrete sounds of a language.
As such, it is the study of spoken language. Written language is only an approximation of spoken language. You can see why we can't quite deal with phonology with regular written alphabets. It's a lot of fun and quite valuable to linguists, but it is only loosely connected with grammar, so we won't often mention it this term. Morphology is the study of basic meaning-bearing units in a language.