It’s a code you enter into a game, or more recently, a website to get an easter egg or extra functionality.
Read more at: http://en.wikipedia.org/wiki/Konami_code
List of Konami websites:
http://konamicodesites.com/
List of Konami games:
http://en.wikipedia.org/wiki/List_of_Konami_code_games
IT stuff 4 u 