In sports, a coach or manager is an individual involved in the
direction and instruction of the on-field operations of an team
or of individual player. Coaching entails the application of
sport tactics and strategies during the game or contest itself,
and usually entails substitution of players and other such
actions as needed. Most coaches are former participants in the
sports in which they are involved, and those who are not have
usually had extensive training in the sport in question. A
coach, particularly in a major operation, is traditionally aided
in his efforts by one or more assistants known as the coaching
staff. The coach's leadership is often cited, rightly or
wrongly, as one of the prime or even the prime ingredient in
successful efforts by the players under his or her direction.
Many times, in major team sports the principal coach (usually
referred to as the head coach) has little to do with the
development of details such as techniques of play or placement
of players on the playing surface, leav