Globular set

In category theory, a branch of mathematics, a globular set is a higher-dimensional generalization of a directed graph. Precisely, it is a sequence of sets formula_1 equipped with pairs of functions formula_2 such that
(Equivalently, it is a presheaf on the category of “globes”.) The letters ""s", "t"" stand for "source" and "target" and one imagines formula_5 consists of directed edges at level "n".
A variant of the notion was used by Grothendieck to introduce the notion of an ∞-groupoid. Extending Grothendieck's work, gave a definition of a weak ∞-category in terms of globular sets.