According to William Caplin, there are only three basic types of cadences in the classical style: two authentic cadences and one half cadence.^[William E. Caplin, *Analyzing Classical Form: An Approach for the Classroom* (New York: Oxford University Press, 2013), 56.] - [[perfect authentic cadence]] - [[imperfect authentic cadence]] - [[half cadence]] In addition to these three cadential types, [[music theory textbooks]] frequently include the [[plagal cadence]]; however, Caplin argues that the plagal motion $\mathrm{IV→I}$ does not constitute a cadence in the classical style.