This document discusses different branches of semantics, the study of meaning in language. It outlines four main branches: 1) lexical semantics which studies word meanings, 2) grammatical semantics which looks at how meaning relates to syntax, 3) logical semantics which models natural language using logical systems, and 4) semantics as it relates to other disciplines like philosophy, anthropology, psychology, and communication theory. The document also discusses Charles Sanders Pierce's three-way distinction of signs as icons, indexes, or symbols and how semantics interacts with other linguistic fields like etymology, lexicology, and discourse analysis.