This book explains discover ways to formally describe programming languages using the strategies of denotational semantics. The presentation is designed primarily for laptop science school college students considerably than for (say) mathematicians. No info of the thought of computation is required, nevertheless it would help to have some acquaintance with high diploma programming languages. The selection of supplies is based on an undergraduate semantics course taught at Edinburgh School for the previous couple of years. Enough descriptive strategies are coated to cope with all of ALGOL 50, PASCAL and totally different comparable languages. Denotational semantics combines a robust and lucid descriptive notation (due primarily to Strachey) with a classy and rigorous precept (on account of Scott). This book presents an introduction to the descriptive strategies with out going into the background arithmetic the least bit. In some strategies that could be very unsatisfactory; reliable reasoning about semantics (e. g. correctness proofs) cannot be completed with out understanding the underlying model and so learning semantic notation with out its model precept could be argued to be pointless. My very personal feeling is that there is a lot to be gained from shopping for a purely intuitive understanding of semantic concepts together with manipulative competence inside the notation. For these equip one with a robust conceptua1 framework-a framework enabling one to visualise languages and constructs in a classy and machine-unbiased means. Perhaps an outstanding analogy is with calculus: for lots of smart features (e. g. engineering calculations) an intuitive understanding of strategies to distinguish and mix is all that is needed.