The difference between a confident and a conceited person is largely his level of self-esteem.
A confident person believes that he is capable and worthy. He does not need to prove his value to others or himself by seeking attention or showing-off because he is secure and takes a positive attitude towards his achievements. Meanwhile a conceited person generally has low-self esteem and showcases what he feels to be superior qualities to prove his worth to himself and to others.
Confident people are generally equipped with good interpersonal skills.
If you like yourself, you expect others to like you, and are therefore more inclined to adopt honest, open and trustworthy behavior patterns. Meanwhile, conceited people may subconsciously look down on themselves, which often translates into negative interpersonal skills such as callous, self-centered behavior that can be off-putting to others.
Application of Abilities
A confident person is more likely to apply her abilities in a way that benefits others.
Since a confident person does not need to seek affirmation of her worth and does not need to place herself above others, she is more likely to direct her attention towards the needs of other people. Meanwhile a conceited person is usually more concerned with herself, since conceit is based on placing yourself above others. As a result, she is more likely to use her abilities in a self-serving manner.
Attitude Towards Failure
A confident person is better than a conceited person at accepting failure and setbacks in daily life and maintaining a positive outlook.
This is because a confident person has an inherent believe in his own worth and understands that faltering is a part of life. Since most conceited people must constantly demonstrate their superiority, they are likely to respond in a negative or angry manner even to minor failures, since their belief in their abilities is not stable.