If its in the
list then it is saved in your notebook:
http://cintanotes.com/help/#notebooksIf you mean when your typing a note in the note window,
not until you press OK:
http://cintanotes.com/help/#taking .
And in addition, when you press Ctrl-S. Or, when pressing Escape and OK on a dialog box if Options>Edit>Save on Esc is unchecked, which it is initially, but I couldn't find about these last two cases it in the Help file while I just quickly skimmed over it.
For your question 'is save automatic' the answer is not clearly extracted from just reading the help file. (There is no 'auto-save' that I know of.) The help file says "press “OK” (or Ctrl+Enter) to add the note to your notebook." which essentially means it is saved, because the notebook is a file.