A sheaf is a collection of items, typically stalks of grain, that are bound together. This method of gathering is often used in agriculture to facilitate the storage and transportation of crops after harvesting. Sheaves can also refer to bundles of paper or other materials that are grouped for organization. In mathematics, particularly in topology and algebraic geometry, a sheaf is a tool that associates data to open sets of a space, allowing for the study of local properties. This concept helps mathematicians understand how local information can be pieced together to form a global picture.