What is the difference between rectangular and hierarchical data in ATUS-X?

What is the difference between rectangular and hierarchical data in ATUS-X?

The ATUS-X data access system delivers rectangular data by default. The rectangularized data file does not retain households or activities as separate records. Household information is put on the person records of each individual in the household. Time use variables created in the system consisting of aggregated time spent in user-specified activities are also delivered on the person record. With rectangularization, there are no separate household, activity, or who records in the data extract. No information is lost, and most researchers prefer this format

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The rectangular format default can, however, be overridden to yield hierarchical data consisting of household records followed by the person records of household members, activity records of ATUS respondents, and who records that accompany activity records. Users who request hierarchical data will need to select variables for inclusion in their extracts from the activity and who records. This is done on the same page in the extract builder as the selection of household and person level variables.