Intonation

In linguistics, intonation is variation in pitch used to indicate the speaker's attitudes and emotions, to highlight or focus an expression, to signal the illocutionary act performed by a sentence, or to regulate the flow of discourse. For example, the English question "Does Maria speak Spanish or French?" is interpreted as a yes-or-no question when it is uttered with a single rising intonation contour, but is interpreted as an alternative question when uttered with a rising contour on "Spanish" and a falling contour on "French". Although intonation is primarily a matter of pitch variation, its effects almost always work hand-in-hand with other prosodic features. Intonation is distinct from tone, the phenomenon where pitch is used to distinguish words (as in Mandarin) or to mark grammatical features (as in Kinyarwanda).

source: [WikiPedia](https://en.wikipedia.org/wiki/Intonation_(linguistics)