Self-development, or personal development, covers all activities that one undertakes to improve one's life;
Done propertly, self-development takes place over the course of a person's entire life.
There are many ideas surrounding personal development, one of which is Abraham Maslow's process of self-actualisation. Maslow (1970) suggests that all individuals have an in-built need for personal development which occurs through a process called self-actualisation.
For Maslow, the path to self-actualisation involves being in touch with your feelings, experiencing life fully and with total concentration.
Personal Development ( Wikipedia )
Maslow, A. H. (1970), Motivation and Personality, (2nd Edition), Harper & Row, New York.