You can choose : Year, Full month, Work month, Full week, Work Week, Day, Upcoming, Changes and matrix view(s)
Only one viewtype can be selected at a time.
When selection is done, You click "done", and You are back to the calendar in the selected view.
You can set up the calendar with URL parameters.
With parameter cP the default view can be set (e.g. year: cP=1, month: cP=2, . . . ,upcoming: cP=7)
You can choose the view ( Year, month, day ) in three ways :
Select the view in options OR
Via settings, set up buttons in navigation bar OR
"drill down" by clicking on a month, week or day, and then "step up" by clicking between the black triangles.
It is Your choice !