In linguistics, intonation is variation of spoken pitch that is not used to distinguish words; instead it is used for a range of functions such as indicating the attitudes and emotions of the speaker, signalling the difference between statements and questions, and between different types of questions, focusing attention on important elements of the spoken message and also helping to regulate conversational interaction. It contrasts with tone, in which pitch variation in some languages does distinguish words, either lexically or grammatically. (The term tone is used by some British writers in their descriptions of intonation, but this is to refer to the pitch movement found on the nucleus or tonic syllable in an intonation unit – see Intonation in English: British Analyses of English Intonation, below).