To build a solid foundation for study, you need to familiarize yourself with the relevant terms.
There is also a quiz to test world common sense.

[Recommended for these people]
Students interested in studying world history,
It is recommended for all those who study in culture after becoming an adult.

[A word from the developer]
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Customers who are burdened with paid apps
Please use the free app.

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The free app inevitably contains numerous ads.