Programming the Semantic Web

I finished reading through chapter 6 so far... my overall impression is, reasonable, but feel inadequate. There are some discussion I like: for example, the simple triple store implementation is illustrative, concept wise. However, the discussion on RDF serialization format, the example given, ontology, it just feels the words are hard to swallow. You would think a book about semantic should have very precise logic and explanation should be crystal clear. However, as I read it, I often get the feel something ... "this should be this hard to explain, what is he talking about here?" ... maybe I am expecting too much.