This version has been archived. Please see the version updated for Joomla 5, 6 and 7: https://github.com/ceford/cefjdemos-com-countrybase
com_countrybase is a Joomla 4 component designed to accompany a tutorial on the Anatomy of an MVC Component.
It displays a list of countries with some currency exchange rate data. It can be used in its own right, although it would need a plugin to update the exchange rates on a daily basis, or used as a basis for something more elaborate.