Confidence is a strong believe in oneself that enables the individual to face the circumstances that is put in front of her. If all things fail, if you are confident enough, there is still hope. Do not let it slide from you. Grab hold of it tightly when it is slipping away. In any situation, if you are confident that you can do it, you will most likely be able to. Well, provided you do have the necessary knowledge or skills to perform any said tasks. Armed with only blind confidence and entering a battlefield is suicidal.
This key factor usually comes from reaffirming yourself that you are capable and that you are able to deliver or by the many compliments of others or perhaps, past successful experiences. The believe in oneself is then manifested into your movements, thoughts, actions and speech thus projecting a persona of confidence which is always key in achieving success in anything you do.