A cell was a small organizational unit, a subset of the whole, either in physical objects, or in concepts and organizations. In politics, a cell structure was often used as a method for organizing a group of people in such a way that the movement could more effectively resist penetration by an opposing organization. Cells often worked independently of each other and members of various cells often had little to no knowledge about the location or identities of other cells and cell members. Thus, when one cell was exposed or captured, the whole movement was not jeopardized. A cell structure was often used by criminal organizations, undercover operatives, intelligence networks, and terrorist insurgents.