Rollback

From time to time when game developers update a game, they accidentally introduce errors in the way the game works either on program level or how the user interacts with the game. This is normally referred to as a bug.
Some bugs can be minor as they may keep the player from doing something that they should, under normal circumstances, be able to do. Unfortunately there are some bugs that can destabilize the game in major ways. These kinds of bugs are referred to as destructive bugs (see Types of Bugs for more information). In short, they include bugs that either damage player or item data, or that severely damage game balance.
Some bugs are easily fixable (an overpowered spell for instance) as once a fix is made, there is no lasting harm. However, a massive influx of money (kamas), item duplication, or a bug that allows players to hack other characters all would cause irreparable damage to the game world. In severe cases such as these, game developers will often resort to a "Rollback".
A Rollback is where the game developers will "restart" the game with the most recent undamaged backup files. The developers will then correct the bug(s) before this clean version of the game is made available to the players again. The concern with performing a Rollback is that all player progress and game world changes made after the save file will not exist, being effectively lost. Rollbacks are an uncommon but always present possibility in MMORPGs, as game developers only use them as a last resort to fix a problem because of the loss of player data and progress.
Usually players will receive a Compensation Gift after a rollback.
For a brief note on Rollbacks from a general computer-science point of view, please see this wikipedia article.
Category:Game information