The data of descriptive linguistics can be derived from any or all of these features and results of behavior-by observing the articulatory motions of the speaker, by analyzing the resulting airwaves, or by recording what the hearer (in this case the linguist) hears. In the first case we obtain modifications of the air-stream in the course of the speaker’s breathing; in the second case we obtain complex wave forms; in the third, impressionistic identifications of sound sequences. Descriptive linguistics deals not with any particular one of these records of behavior, but with the data common to them all; for example, those frequencies or changes in the air-waves to which the human ear does not react are not included in the data of linguistics.
- Harris (1951), a pag.5

[…] most of the data consists (by definition) of whole utterances, including longer stretches which can be described as sequences of whole utterances.
- Harris (1951), a pag.11