Organization is like system a very broad and ambiguous name with a wide variety of synonyms, for example alignment, arrangement, composition, configuration, coordination, design, group, structure or system. It is used to characterize an organized and ordered structure or system, where the elements are arranged in a non-random way, and it can also describe the order itself.
An organization in social systems (an organization of agents) has a purpose, a particular end it is trying to achieve. Agents who join the organization must serve the same purpose. Such an organization is a formal group of people, persons or agents with one or more shared goals which act together in order to reach these goals. Organizations are usually hierarchical structured to avoid the circular passing of responsibility. A tree-like command structure without loops is helpful to avoid 'delegation loops' and confusion.
These organizations are different from organization which arises by spontaneous order, which has no purpose. Self-Organization describes the organization without organizer in natural or artificial systems.