Short answers, pulled from the story.
Final Fantasy XIII was released in Japan on the 17th of December 2009 and in North America, Europe, and Australia on the 9th of March 2010, for PlayStation 3 and Xbox 360. A Windows version followed in October 2014, and the game was added to Xbox One backward compatibility in November 2018.
As of 2017, Final Fantasy XIII had sold over 7 million copies worldwide on consoles. The Windows version sold over 746,000 copies according to SteamSpy. The entire Final Fantasy XIII series had shipped over 11 million copies worldwide as of September 2014.
Masashi Hamauzu composed the soundtrack for Final Fantasy XIII. The score was partially orchestrated with the Warsaw Philharmonic Orchestra. Final Fantasy XIII was the first main-series game in the franchise to include no compositions by series veteran Nobuo Uematsu.
The Crystarium is the leveling system in Final Fantasy XIII, built around six crystals corresponding to the six character roles. Each crystal is divided into ten levels containing nodes that grant bonuses to health, strength, or magic, or unlock new abilities. Players advance through the system by spending Crystogen Points earned from defeating enemies.
Critics and players objected to the game's narrow corridors, removal of explorable towns, and limited interaction with non-player characters, especially in the first ten chapters set on Cocoon. Some reviewers described the experience as following a hallway toward a target symbol on the minimap. Director Motomu Toriyama later said the linear structure was a deliberate storytelling choice, arguing that open-world freedom made it harder to tell a compelling story.
Final Fantasy XIII was directed by Motomu Toriyama and produced by Yoshinori Kitase, both of whom had previously worked together on Final Fantasy X and X-2. The main character designs were handled by Tetsuya Nomura, who had performed the same role on Final Fantasy VII, VIII, X, and X-2.