"Two main things contribute to self-confidence: self-efficacy and self-esteem. We gain a sense of self-efficacy when we see ourselves (and others similar to ourselves) mastering skills and achieving goals that matter in those skill areas. This is the confidence that, if we learn and work hard in a particular area, we’ll succeed; and it’s this type of confidence that leads people to accept difficult challenges, and persist in the face of setbacks. This overlaps with the idea of self-esteem, which is a more general sense that we can cope with what’s going on in our lives, and that we have a right to be happy. Partly, this comes from a feeling that the people around us approve of us, which we may or may not be able to control. However, it also comes from the sense that we are behaving virtuously, that we’re competent at what we do, and that we can compete successfully when we put our minds to it."

Building Self-Confidence - Prepare yourself for success - Stress management skills from Mind Tools