why island tables?

[Akina0929]

Hi,

    I know what is island tables but don't know why island table please let know  in interview point of view.

thanking you,

[rupamjyotidas]

Data islands can be created from any data source and are often created as an inline table. Data islands can be used to reference dates, table headers, or whatever you need to be disconnected from most of the existing data in the data model.

[settu_periasamy]

see this discussion  as well What are data islands?