Source: wikibot/cohomological-descent
= Cohomological descent
{wiki=Cohomological_descent}
Cohomological descent is a concept in algebraic geometry and algebraic topology, which is particularly associated with the study of sheaves and cohomology. It captures the idea of how properties of sheaves (or more generally, objects in a category) can be characterized in terms of local data, often related to covering spaces or open covers.