The ego, as mentioned here, refers to the unconscious stream of thought that many people incorrectly identify themselves with as individuals.

This is also referred to as the human mind or unnecessary thinking.  It is a barrier to becoming aware and acknowledging the current moment because of its tendency to focus on identification with the past or future.

Examples of an alternative state, in which one realizes that one can observe the egoic thought, and therefore cannot be the actual sum of these thoughts, but at least an observer of the thoughts, surface in everyday life from Buddhists who use the concept of ‘no mind’, the athlete who ‘stops thinking’ to ‘enter the zone’, or even the peaceful feeling between egoic driven moments when we perform mundane tasks without the anticipation of some future moment.