The meta menu (top right, see Overview) contains mainly supporting functions outside the core functionality:

From left to right:

Fiscal period [more]
Here you can switch between the different fiscal periods, create new ones, complete and reopen them.

User [more]
This is where your user name is displayed and you can adapt your personal user profile or log out of the application.

Organization [more]
The name of the current organization is displayed here and you can switch between your organizations and create new ones. As administrator you can also manage the current organization and its users & roles.

Settings [more]
Here you can change general settings. Also you'll find help (this manual) and support here.