The term prosody refers to the elements of speech that can be heard and are other than words or phonemes. We define prosody as the "musical attributes of speech" that can be heard as "melody ..., rhythm, dynamics, tempo, and pausing" ("Part Two: Notes on Prosody," King's College London). Such musical elements are used to express emotions, just as laughter and pauses express emotions; therefore prosody is essential in interpreting discourse; it can even be said that conversations do not truly exist without prosody. As laid out by King's College London's "Notes on Prosody," there are 7 different prosody features used in interpreting discourse:
1. Intonation, which refers to the variation in pitches, meaning the changes in notes, in syllables as words are spoken.
2. Variations in loudness, which are created by raising or lowering voices.
3. Variations in stress, which refers to the changes in emphasis of syllables in words, phrases, or sentences.
4. Variations in vowel length such as we see in the difference between short vowels and long vowels.
5. Tempo, defined as the speed at which sounds are made, and pausing, which are stops between sounds.
6. Variations in pitch register, which refers to the changes in the overall pitch of a voice throughout a discourse as opposed to the pitch of individual tones.
7. Rhythm, which is a cyclical pattern that occurs over a span of time; in linguistics, such patterns are created through changes in stress and intonation.
Throughout discourse, we continually, intuitively use prosody to interpret meaning in an utterance, which is a unit of speech. We use prosody to analyze utterances by grouping words and phrases, picking out main phrases, following the flow of an argument, choosing possible meanings, and interpreting or communicating attitude. One example of prosody analysis can be seen in the fact that the same phrase of words can be stated as a question, a simple statement, or as a command, and meaning changes with each. Specifically, the phrase "finish the report" can be asked as a question, made into a simple statement of fact concerning tasks to be done, or even stated as a command to a subordinate, and meaning changes significantly in each case.
Rather than differentiating between the normal utterance and the emotional utterance, the field of linguistics differentiates between the linguistic prosody and the emotional prosody. Linguists define emotional prosody as "the ability to express emotions" (Raithel, V., & Hielscher-Fastabend, M., "Emotional and Linguistic Perception of Prosody," Folia Phoniatrica et Logopaedica). In contrast, linguistic prosody is the ability to eliminate ambiguity, the ability to recognize intentional organization of words or other parts within a sentence, the ability to recognize intonation contours within a sentence, meaning changes in tone, pitch, and stress. Both emotional and linguistic prosody rely on the same features of tempo, pitch, and loudness for interpretation.