The process of determining the quantity of a substance A by adding measured increments of substance B, with which it reacts (almost always as a standardized solution called the @[email protected], but also by electrolytic generation, as in coulometric titration) with provision for some means of recognizing (indicating) the endpoint at which essentially all of A has reacted. If the endpoint coincides with the addition of the exact chemical equivalence, it is called the equivalence point or @[email protected] or theoretical endpoint, thus allowing the amount of A to be found from known amounts of B added up to this point, the reacting @[email protected] ratio of A to B being known from @[email protected] or otherwise. Terms for varieties of titration can reflect the nature of the reaction between A and B. Thus, there are acid–base, complexometric, chelatometric, @[email protected]–reduction, and @[email protected] titrations. Additionally, the term can reflect the nature of the @[email protected], such as acidimetric, alkalimetric, and iodometric titrations as well as coulometric titrations, in which the @[email protected] is generated electrolytically rather than being added as a @[email protected]