What is this thing called WWW server?

In many parts of the world, the serving player is allowed the privilege of adding or removing elements from gameplay that may make it easier for him or her to remain in the game, or to make it easier to get an opposing player eliminated. At the start of each round, the server is entitled to change these rules, and is expected to annouce and/or explain what the new rules will be. Games with beginners generally choose to ban difficult moves, and more experienced players make up more complicated rules.