A clandestine cell structure is a method for organizing a group of people like resistance fighters or terrorists in such a way that it can more effectively resist penetration by an opposing organization (e.g., a law enforcement organization). In a cell structure, each small group of people in the cell only know the identities of the people in their cell; as such, if a cell member is apprehended and interrogated, he or she will not know the identities of the higher-ranking individuals in the organization. Depending on the group's philosophy, its operational area, the communications technologies available, and the nature of the mission, it can range from a strict hierarchy to an extremely distributed organization. It is also a method used by criminal organizations, undercover operatives, and unconventional warfare (UW) units led by special forces. Historically, clandestine organizations have avoided electronic communications, because signals intelligence is a strength of conventional militaries and counterintelligence organizations.