A subscript or superscript is a number, figure, symbol, or indicator that appears smaller than the normal line of type and is set slightly below or above it – subscripts appear at or below the baseline, while superscripts are above. Subscripts and superscripts are perhaps best known for their use in formulas, mathematical expressions, and descriptions of chemical compounds or isotopes, but have many other uses as well.
In professional typography, subscript and superscript characters are not simply ordinary characters reduced in size; to keep them visually similar to the rest of the font, typeface designers make them slightly heavier than a reduced-size character would be. Likewise, the amount that sub- or superscripted text is moved from the original baseline varies by typeface and by use.
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.