Classify the comparison
Social stratification ranks positions unequally through dimensions such as wealth, power, and prestige. Movement between those positions and the existence of the ranking are distinct questions.
Social mobility describes movement within a society’s hierarchy. Intragenerational mobility compares positions during one person’s life. Intergenerational mobility compares people with their parents’ generation. These comparisons need not give the same result.
A hypothetical career
Suppose someone starts as a trainee and later becomes a supervisor. An improvement in occupational position during that career is upward intragenerational mobility. Comparing the supervisor’s position with their parents’ occupations instead asks an intergenerational question.
A job change with similar status may be horizontal movement. A change associated with lower status can be downward mobility. Salary alone does not settle every classification, because occupations, prestige, and other dimensions can move differently.
Personal movement and structural change
Expansion or contraction of an industry can change opportunities for many people together. Structural mobility concerns such wider changes, rather than explaining every outcome through individual effort.
Mobility does not imply that hierarchy has disappeared. People may move between positions while substantial inequalities between those positions persist. State which dimension and time comparison you use before drawing conclusions.
Related question
Apply this knowledge
Use the concept guide to understand the reasoning, then return to the complete question and worked answer.
What Is Stratification? A One-Sentence Sociology DefinitionSources
These references support the core concepts and interpretation boundaries explained above.