Stealth Technology

Stealth or low observability (it is scientifically known) is the technology that allows an object (aircraft or missile) to be partially invisible to Radar or any other means of electromagnetic detection. The motive behind incorporating stealth technology in an aircraft is to make it invitility by making it less visible. 

The technology was initially developed by US it was the first country to use stealth technology. The first stealth aircraft was F-117 "Night Hawk" developed by Lockheed Martin (United States). The technology involves, superior designs of defense weapons and the use of advanced materials and paint coat, so as to make the surface of missiles or aircraft's less reflective or non- reflective to electromagnetic radiations (EMR) beamed by enemy's radar. 

In simple terms, The Stealth bombers unusual shape and its composite construction material have made it virtually undetectable by current radar systems.