Index cards are a folder, or substorm, containing other stickies and ideas inside of it. When you delete your index card, you are deleting all of the data inside of it too.
- Click once on the open space in the top bar of the Index Card. 
- Click Delete in the pop-up menu to delete the Index Card. 
Deleted index cards and the stickies inside of them can be recovered from your trash if they were deleted by mistake.
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