Private sector computer repair technicians can work in corporate information technology departments, central service centers or in retail computer sales environments. Public sector computer repair technicians might work in the military, national security or law enforcement communities, health or public safety field, or an educational institution. Despite the vast variety of work environments, all computer repair technicians perform similar physical and investigative processes, including technical support and often customer service. Experienced computer repair technicians might specialize in fields such as data recovery, system administration, networking or information systems. Some computer repair technicians are self-employed or own a firm that provides services in a regional area. Some are subcontracted as freelancers or consultants. This type of computer repair technician ranges from hobbyists and enthusiasts to those who work professionally in the field.