what is s.ytimg.com
YouTubeIMaGe – s.ytimg.com means YouTube image
https://support.mozilla.org/en-US/questions/953550
This is a tracker that you can change as follows https://support.mozilla.org/en-US/kb/enable-and-disable-cookies-website-preferences
If you place YouTube videos on you website, you may not want to place them on your Home Page for speed considerations, as this tracker tends to be the slowest component. Check that here http://tools.pingdom.com/fpt/ Pingdom website Speed Test
Personally hate Adobe for its methods so learn about and change those here http://help.adobe.com/en_US/FlashPlayer/LSM/WS6aa5ec234ff3f285139dc56112e3786b68c-7fff.html