This thesis studies both the meaning and logic of different expressions and sentence types. For example, names (“Spud”), predicates (“is a cat”), imperative sentences (“Shut the door!”), deontic modals (“Must”, “May”), meaning claims (“Triangle means three-sided shape”) and knowledge attributions (“Spud knows you’re home”). It does this from a perspective that understands meaning in terms of norms of language use. In most chapters of the thesis these norms are formalised in proof-systems but some parts are non-formal (non-mathematical). For many of these topics, there hasn’t been work done on them previously from this perspective.