Wipe

It usually comes "soon", and erases all player characters, caps, items, bases, tents, factions, etc. After a wipe, all players start over and a new season begins. It is a data purge of part of server database, where player information is stored.

A temporary time called "Pre-Wipe Madness" may occur for perhaps a week or two immediately prior to a wipe, when crazy things happen. Hidden locations like tents and bases might be exposed for all players to see, creating opportunities for sudden, intense PvP battles where such normally do not occur. Bases get raided and items are stolen, but who cares? It's all about to be wiped at that point anyway. Rare items can be found and game staff might even place Power Armor barely out of sight in the streets of major towns, for any of us to find. Sometimes hundreds of items are dropped on a town map like flowers, Small Statuettes, drugs, rare guns and ammo, etc. Pre-Wipe Madness is temporary crazy fun and usually draws in some of the stagnate players who are waiting for the next season.

Developers opinion:

But there is no date set and no wipe planned. If a wipe has to come, we will announce it some time before.
Source: (http://fonline2238.net/forum/index.php?topic=1464.15)