Here, you can see all calendar entries, you made.
If you wish to have a look which notifications you have for today, just press 
button and they'll be marked.
You can save your data on the disk, or in the phone memory, what ever you choose.
Also, there's possibility to recurrence calendar entries hourly, daily, weekly, monthly and yearly. If there's no such possibility in your phone, entries will be written to it one by one, not like a single. Such entries are marked with 
symbol. There also are two special buttons on the toolbar, that helps to open/close those entries 
. After writing changes to the phone and then back to the program, you'll see several entries, not the one, as it was.
There is possibility to Import your Calendar to the Microsoft Outlook and Export it back. You can do that with all events, or just selected.
See also:
Working with Oxygen Phone Manager for Nokia phones