This document discusses semantics and meanings in language. It defines semantics as the study of meaning in words, phrases, and sentences. Meaning exists in the mind and we express meaning through language. Philosophers have debated the relationship between words and their meanings for over 2000 years. More recently, thinkers have argued that the meaning of a word is the concept it represents in the mind rather than the object itself. The document goes on to discuss different types of meanings including denotative meaning, social meaning, thematic meaning, and sentence versus utterance meaning. It also covers topics like semantic roles, ambiguity, sense and reference, entailment, and presupposition.