Normal weapons are the most common type of weapon. They are sold from various NPCs up through level 85, and drop from monsters more frequently than the other types of weapons.
Rare weapons have special bonuses, as well as a higher attack rating than normal weapons. They cannot be bought from any NPCs, but can be obtained from monster drops and some quests.
Unique weapons are among the most powerful in the game and are highly sought after. They are not sold from any NPC, and with the exception of Bloody weapons, drop only from Giants. They can also be made with the crafting system. Uniques are the only weapons that can be turned into Ultimate Weapons.
Once a soul-link item is equipped by a player, it becomes soul-linked to that player and cannot be traded, sold, banked, warehoused, dropped, or mailed. Soul-link weapons are the rarest in the game, obtainable only through specific dungeon boss monster drops.
These weapons drop from their respective bosses as Ultimate Weapons.
Baruna weapons utilize the Baruna Upgrade System. Unlike the previous soul-link weapons, these do not drop as ultimates, and neither can they be converted to ultimates - no form of upgrading or enhancement may be used on baruna weapons other than the Baruna Upgrade System.