In order to stop Facebook notifications, you will need to visit your Facebook account and change your settings there. You can enable or disable the notifications you'd like to receive. For more information, please visit Facebook's help pages at:

    http://www.facebook.com/help

Alternatively, you can use filters to sort the messages you receive in Yahoo! Mail. With filters, you can move messages that meet specific criteria to a folder of your choosing or even the Spam or Trash folders. Note that filters must be configured while using a desktop or laptop computer, and cannot be set up from a mobile device. To learn how to create filters, please visit this help page.