Press the Enter key in the middle of a game to display the chat field.
Age of Empires 2 is a PC game in which you build up towns full of citizens and soldiers, and win by either meeting certain objectives or by conquering your opponents. Building up and maintaining towns and their various stores and posts requires the player to create citizens (or "men") but the number of men you can create depends on your food supply. By using a cheat to continuously replenish your food supply you'll be able to create unlimited men in the game.
Type the following code into the chat field: pepperoni pizza. Press the Enter key to submit the code. This will give you 1,000 food.
Click the villager icon at the bottom of the screen to create more men. If you're told you can't make any more, bring the chat field up and enter the code a few more times to gather enough food to make more men. If you repeat this process, you can create an infinite number of men.