Stump's Programming Language Foundations is a short concise text that covers semantics, equally weighting operational and denotational semantics for several different programming paradigms: imperative, concurrent, and functional. Programming Language Foundations provides: an even coverage of denotational, operational an axiomatic semantics; extensions to concurrent and non-deterministic versions; operational semantics for untyped lambda calculus; functional programming; type systems; and coverage of emerging topics and modern research directions.