panel data

cross sectional data
time seires data
and the mixed one! panel data


Panel data, sometimes referred to as longitudinal data, is data that contains observations about different cross sections across time. Examples of groups that may make up panel data series include countries, firms, individuals, or demographic groups.
Like time series data, panel data contains observations collected at a regular frequency, chronologically. Like cross-sectional data, panel data contains observations across a collection of individuals.

-출처
https://www.aptech.com/blog/introduction-to-the-fundamentals-of-panel-data/