This document provides an overview of phonetics, which is the study of speech sounds and their production, perception, and physiology. It discusses phonetics as a science that focuses on the smallest units of language. The document then describes the three main branches of phonetics: acoustic (sound waves), auditory (perception), and articulatory (production). It goes on to explain places and manners of articulation, identifying different speech sounds based on where and how they are produced in the vocal tract. Various speech sounds are defined using phonetic symbols. In closing, the document provides references for further reading on linguistics and phonetics.