In North Korea, your rank is fixed before you are born
What was supposed to create perfect fairness became about 50 hereditary ranks, with one man treated as a god at the top.

North Korea set out to build the most equal society on Earth, and ended up sorting every baby into a hereditary rank before birth.
That is how Yeonmi Park, who escaped North Korea and now speaks about life under the regime, describes the Songbun system. It is a family caste system, inherited through the family, in which Park says a person's life is determined before birth.
It works in two layers. At the top are three broad groups, which Park names as the core, the wavering, and the hostile. Beneath those, the population is divided into 50 different classes.
The exact ranking is kept in a secret government document, Park says, so many people do not even know precisely where they sit. Officials do, and Park says that is how they decide your future.
Park's shorthand for what happened is blunt. The leaders "dreamed of creating the most equal society," Park says, and ended up with what she calls the most unequal society, with one man at the top who became a god.
Questions people ask
Can a North Korean move to a higher class by working hard?
No. In North Korea the class is inherited through the family and recorded by the state, so a child receives the family's standing at birth. Advancement through school or work does not erase that starting assignment.
How is this different from a caste system like India's?
India's historic caste system was rooted in religion and occupation, and India's constitution now bans caste discrimination. North Korea's system is political, assigned and tracked by the state to decide a person's future.