stratification

Imagine a layered cake: that gives you the basic idea. The word describes the way something is arranged in clear layers or levels. In geology, it refers to rock layers. In society, it describes how people are separated into social classes or groups. It can also suggest ranking, where some groups have more power, money, or status than others. In research, a stratified sample means choosing people from different groups in a population so the sample better reflects the whole group. You might say a city shows clear social stratification by income and neighborhood.

At its heart, stratification is about layers. It is the process or state of being arranged into distinct levels or strata. In geology, this can mean rock formations built up over a long time, with each layer showing a different period in Earth's history. That is also where the word comes from: stratum means "layer" in Latin.

However, stratification is not limited to rocks. It is widely used in the social sciences to describe how societies are organized into levels based on wealth, status, power, and occupation. Social stratification refers to the unequal distribution of resources and opportunities across different groups within a society, often creating "upper," "middle," and "lower" classes.

The word also extends beyond geology and society. In biology, you might talk about the stratification of a forest canopy, with different plant species growing at different heights. In statistics and research, stratified sampling is a method used to create a more representative sample by dividing a population into subgroups, or strata, before randomly selecting participants from each one.

The key idea is that stratification involves a system of levels. Sometimes the levels are simply physical layers, and sometimes they show important differences in rank, access, or role. It is not just about having layers; it is also about the distinctions between them. So whether you are studying rocks, societies, forests, or research methods, the word points to something organized into separate levels.