Balance is essential for all physical development and is a prerequisite  for almost every movement skill.  It is sub-divided into two categories:  

1.  Static balance: the ability to maintain a static position throughout a movement (e.g. a handstand in gymnastics).

 2.  Dynamic balance: controlling the body when moving (e.g. keeping the body stable while kicking a football).

This resource focuses on the single leg static balance (T-balance).  All movements require some form of static balance, which is managed through effective posture and a combination of muscular contraction and relaxation.  When balancing on one leg, the centre of gravity needs to be over the base of support.  If a body part is extended away from this centre of gravity, then the body needs to compensate with an extension in the opposition direction, thus maintaining the centre of gravity over the base to keep the balance stable.  The wider the base of support, then the easier it is to balance.  The single leg static balance has a small support base so it is essential to first begin with large-based balances as a prerequisite to this skill.