EN
In this article considered was issue of special services, which became particularly interesting after the Second World War. Made was an attempt of characterizing methods used by special services, and of formulating general definitions of terms associated to them, such as: intelligence services, spy, diversion and sabotage. Considered was also an unevident relation of special services to terrorist activity, especially the so called cyberterrorism, which in the article was characterized through indication of most common methods of such actions. Relevant for the article is also issue of security and information protection, particularly legal ways of fighting terrorism and activities of foreign special services.