The Samsung Galaxy Note 5 is shipped with a nifty feature called Screen off memo, which is meant to boost the capabilities of the S Pen. Users can now take quick notes from the lock screen.
How To Use Screen Off Memo on the Galaxy Note 5
In order to use this feature, you'll need to enable it in your phone's settings. Go to Apps > Settings > Device > S Pen and toggle the Screen off memo switch On:
Take Notes Directly on the Note 5 Lock Screen
You can now take notes (memos) without unlocking the screen of your smartphone. Just pull out the S Pen and write the note directly on the lock screen. Simply slide your S Pen back into its slot to save the note (as an action memo in the S Note app).