Intonation (linguistics)

In linguistics, intonation is variation of pitch while speaking which is not used to distinguish words. (Compare tone.) Intonation and stress are two main elements of linguistic prosody.
All languages use pitch semantically, that is, as intonation, for instance for emphasis, to convey surprise or irony, or to pose a question. Tonal languages such as Chinese and Hausa use pitch to distinguish words in addition to intonation. 
"Rising intonation" means the pitch of the voice increases over time; "falling intonation" means that the pitch decreases with time. A "dipping intonation" falls and then rises, whereas a "peaking intonation" rises and then falls.
The classic example of intonation is the question-statement distinction.
For example, northeastern American English, like very many languages (Hirst &amp; DiCristo, eds. 1998), has a rising intonation for echo or declarative questions ("He found it on the street?"), and a falling intonation for "wh-" questions ("Where did he find it?") and statements ("He found it on the street."). Yes or no questions ("Did he find it on the street?") often have a rising end, but not always. Some languages like Chikasaw and kalaallisut have the opposite pattern: rising for statements and falling with questions.
Dialects of British and Irish English vary substantially, with rises on many statements in urban Belfast, and falls on most questions in urban Leeds.
In the International Phonetic Alphabet, "global" rising and falling intonation are marked with a diagonal arrow rising left-to-right and falling left-to-right , respectively. These may be written as part of a syllable, or separated with a space when they have a broader scope:
Here the rising pitch on "street" indicates that the question hinges on that word, on where he found it, not whether he found it. 
Here, as is common with "wh-" questions, there is a rising intonation on the question word, and a falling intonation at the end of the question.