Short answers, pulled from the story.
Final Fantasy XI launched on the 16th of May 2002. This release made it the first massively multiplayer online role-playing game to allow players on PlayStation 2 and Microsoft Windows to share the same digital world.
The five playable races in Final Fantasy XI are Humes, Elvaan, Galka, Mithra, and Tarutaru. Each race was cursed by the God of Twilight, Promathia, with specific flaws such as apathy, arrogance, rage, envy, and cowardice that defined their societal roles and conflicts.
The enmity system in Final Fantasy XI determines a monster's target based on the damage dealt, healing received, and abilities used by players. This mechanic forces players to coordinate their actions in real time to manage aggression and protect fragile party members.
In early 2006, Square Enix permanently banned 700 accounts and removed 300 billion gil from circulation after discovering players exchanging game currency for real money. That July, the company banned or suspended over 8,000 other accounts for similar manipulation and commerce.
The main story of Final Fantasy XI concluded in 2015 with the release of Rhapsodies of Vana'diel. The narrative unfolded over 14 years and began 20 years after the Crystal War.
The music for Final Fantasy XI was composed by Naoshi Mizuta, Kumi Tanioka, and Nobuo Uematsu. A compilation CD box titled Final Fantasy XI Original Soundtrack Premium Box was released on the 28th of March 2007.