The term, operations research was first coined in 1940 by McClosky and Trefthen in a small town Bowdsey, of the U.K. . This new science came into existence in a miliatary context.  During world war II, military management called on scientists from various disciplines and organised them into teams to assist in solving strategic and tactical problems, relating to air and land defence of the country.  Their mission was to formulate specific proposals and plans for aiding the Military commands to arrive at decisions on optimal utilisation of scarce military resources and efforts and also to implement the decisions effectively.  This new approach to the systematic and scientific study of the operations of the systems was called Operations Research. Hence OR can be associated with "an art of winnig the war without actually fighting it."
Essential Charectistics of OR:

i) System orientation ii) Use of interdisciplinary terms iii) Application of scientific method iv) Uncovering new problems

v) Quantitive solutions vi) Human factors

Scope of OR: There is a great scope for economists , statisticians, administrators and technicians working as a team to solve problems of defence by using this approach.  Besides this, OR is useful in the various other important fields like Agriculture, Finance, Industry, Marketing, Personnel Management, Production Management, Research and Development.