Self-esteem is confidence in one's own worth, abilities, or morals. Self-esteem encompasses beliefs about oneself (for example, "I am loved", "I am worthy") as well as emotional states, such as triumph, despair, pride, and shame.^[1] Smith and Mackie define it by saying "The self-concept is what we think about the self; self-esteem, is the positive or negative evaluations of the self, as in how we feel about it (see self)."^[2]

The construct of self-esteem has been shown to be a desirable one in psychology, as it is associated with a variety of positive outcomes, such as academic achievement,^[3][4] relationship satisfaction,^[5] happiness,^[6] and lower rates of criminal behavior. The benefits of high self-esteem are thought to include improved mental and physical health, and less anti-social behavior^[7] while drawbacks of low self-esteem have been found to be anxiety, loneliness, and increased vulnerability to substance abuse.^[8]

Self-esteem can apply to a specific attribute or globally. Psychologists usually regard self-esteem as an enduring personality characteristic (trait self-esteem), though normal, short-term variations (state self-esteem) also exist. Synonyms or near-synonyms of self-esteem include: self-worth,^[9] self-regard,^[10] self-respect,^[11][12] and self-integrity.

Several studies suggest that socially engaged activities can improve adolescents' self-esteem, mental well-being, and overall health. These include volunteering, leadership programs, and participation in youth councils.^{[13][14][15][16][17][18]} In most cases, this positive association depends on participation being voluntary rather than compulsory.^[19] Youth volunteering has also been linked to higher income in adulthood.^[19]

Self-esteem typically declines from ages 4–8 as children compare their real and ideal selves, rises rapidly during adolescence and young adulthood, increases gradually through middle adulthood, peaks around ages 60–70, then declines again in later life.^[20]