An input code for many games, invented and particularly used in Konami games. The code is Up, Up, Down, Down, Left, Right, Left, Right, B, A.

The code is now in over 100 games and has varying effects. Most famously it is used in the game Contra, where it gives the player 30 extra lives. It is frequently featured as an Easter egg in other media to appeal to gamer culture, as countless people have the code memorized.