Clicks are speech sounds that occur as consonants in many languages of southern Africa, and in three languages of East Africa. Examples of these sounds familiar to English speakers are the tsk! tsk! (American spelling) or tut-tut (British spelling) used to express disapproval or pity, the tchick! used to spur on a horse, and the clip-clop! sound children make with their tongue to imitate a horse trotting.
Technically, clicks are obstruents articulated with two closures (points of contact) in the mouth, one forward and one at the back. The enclosed pocket of air is rarefied by a sucking action of the tongue (in technical terminology, clicks have a lingual ingressive airstream mechanism). The forward closure is then released, producing what may be the loudest consonants in the language, although in some languages such as Hadza and Sandawe, clicks can be more subtle and may even be mistaken for ejectives.
Click consonants occur at five principal places of articulation. IPA represents a click by placing the assigned symbol for the place of click articulation adjacent to a symbol for a non-click sound at the rear place of articulation. The IPA symbols are used in writing most Khoisan languages, but Bantu languages such as Zulu typically use Latin ⟨c⟩, ⟨x⟩ and ⟨q⟩ for dental, lateral, and alveolar clicks respectively.