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Roman ordinary vs maronite vs extraordinary calendar

I downloaded an application that provides daily bible texts. Within the app, it is possible to switch between different calendars:
- Roman ordinary calendar
- Maronite calendar
- Extraordinary calendar

I know that the daily bible texts within the catholic church are following the Roman ordinary calendar. But the other two calendars are unknown to me. What I am interested to know:
- Which christian groups use the second and the third calendar in the listing above?
- In which countries the christians can be found that use the second and the third calendar?

Thanks for any explanation.