语音学是研究言语声音（即语音）的学科。狭义的语音学对应英语中phonetics(发音)一词，关切的重点在具体语音本质以及产生语音的方法，与之相对的是音韵学（或称音系学），研究音位或语音区别特征在某种语言中运作的抽象规则和语音的系统。广义的语音学是指这两大方面研究的总合。本文介绍的是狭义的语音学。

语音是语音学研究的客体，指的是人类说话时发出的具体声音，即言语的声音。

语音学的研究范畴包括以下三类：

国际语音学学会所制订的国际音标是语言学界广泛用来标注语音的音标方案。

Phonetics (pronounced /fəˈnɛtɪks/, from the Greek:φωνή, phōnē, 'sound, voice') is a branch of linguistics that comprises the study of the sounds of human speech, or—in the case of sign languages—the equivalent aspects of sign. It is concerned with the physical properties of speech sounds or signs (phones): their physiological production, acoustic properties, auditory pe****tion, and neurophysiological status. Phonology, on the other hand, is concerned with the abstract, grammatical characterization of systems of sounds or signs.