How are self-esteem and self-concept different? What is the origin of these characteristics? What are the characteristics of children and adults with low self-esteem?

Self-esteem is thinking of yourself in a positive life and giving yourself value while self concept is the definition you give yourself as person in whole. I don't quite know the origin of these characteristics but children and adults with low self esteem tend to have traits which relate to timidness, inability to socialize, reserved, etc,.