10 hindrances
There are ten hindrances to Enlightenment (shown below) and four stages of realization (Enlightenment) based on how many hindrances have been eliminated and / or the degree to which they have been eliminated.
A Buddha is someone who is fully enlightened. A person who is fully enlightened, but not The Buddha of our time, is called an Arahant in Pali. Such a person has eradicated all ten hindrances to Enlightenment:
The belief in a permanent personality, ego
Doubt, extreme skepticism
Attachment to rites, rituals, and ceremonies
Attachment to sense desires
Ill-will, anger
Craving for existence in the Form world (heavenly realms)
Craving for existence in the Formless world (heavenly realms)
Conceit
Restlessness
Ignorance
(from Anguttara Nikaya 10.13)
An Anagami (Non-returner) has completely eradicated the first five hindrances and never returns to earth or any other world system (planet, solar system). Such a person is re-born to a heavenly realm and attains Enlightenment from there.
A Sakadagami (once-returner) has eradicated the first three hindrances and greatly weakened the fourth and fifth; attachment to sense desires and ill-will. Such a person will be re-born to either the human or heavenly realm and will attain Enlightenment there.
A Sotapanna (stream-entrant) has eradicated the first three hindrances and will be re-born no more than seven more times and Re-Birth will either be as a human or a deva in a heavenly realm.
