1) Social stratification refers to the division of society into hierarchical social groups based on factors like power, property, and social evaluation. 2) There are two main types of social stratification - ascribed (based on characteristics like gender, family background) and achieved (based on factors like education and occupation). 3) Education can promote social mobility by allowing people to achieve different statuses than their parents and adopt new lifestyles. It also aims to reduce social rigidity and discrimination based on birth.