Adolescent egocentrism describes the tendency for adolescents to have differing perceptions between what they believe others think about them and what other people actually think about them. This is a component of David Elkind's theories on child development which are based on Piaget's theory of developmental cognitive stages.
Adolescents typically think others are more aware and attentive of their behavior and appearance than people actually are. A common way of thinking for an adolescent that trips over the sidewalk at school is that everyone saw them and noticed and are going to think negatively about them for being clumsy. The entire world revolves around them in some manner.
Two components of adolescent egocentrism identified by Elkind are the imaginary audience and the personal fable.
The imaginary audience is essentially a mentally constructed anticipation of an event or situation in a future social setting. A person will imagine how others will react to them and how they will behave in this future setting which forms the imaginary audience. Unfortunately situations rarely work out the way a person imagines because adolescents imagine themselves as the absolute center of attention for the audience and social settings that are rarely this way.
The personal fable is comprised of adolescent beliefs that their feelings are unique and uncommon. They are profound and special and no one can feel the same way that they do. The personal fable often works with the imaginary audience to strengthen an adolescent's egocentrism. Typically these traits fade away as development towards adulthood occurs.