Self Esteem is the experience of being competent to cope with the basic challenges of life and being worthy of happiness. It is the opinion that you have of yourself.
Self esteem is essential for psychological survival. Judging and rejecting yourself causes enormous pain, and you might find yourself avoiding anything that might aggravate the pain of self-rejection in any way. You take fewer social, academic, and career risks. Having low self esteem can mean that you make it more difficult for yourself to meet people, interview for jobs, limit your ability to get close to people, express your sexuality, be the centre of attention, hear criticism, ask for help or solve problems.
How you perceive and feel about yourself can change. You can uncover and analyse the negative self statements that you make and learn to make more realistic and positive ones about yourself.