在数学里的范畴论中，极限的概念融贯了多种构造，包括和、积等等；范畴论中许多泛性质也可从极限来理解。

极限分为极限与余极限（又称上极限），彼此的定义相对偶。在不同场合的别名及英译如下表：

本条目用语取归纳极限与射影极限。

In category theory, a branch of mathematics, the abstract notion of a limit captures the essential properties of universal constructions such as products, pullbacks and inverse limits. The dual notion of a colimit generalizes constructions such as disjoint unions, direct sums, coproducts, pushouts and direct limits.