Short answers, pulled from the story.
Dark Souls was created by Hidetaka Miyazaki and developed by FromSoftware. Miyazaki directed the first and third games, though he stepped back from the director role on Dark Souls II while remaining involved in a supervisory capacity.
The Dark Souls series had shipped over 39 million copies worldwide. Dark Souls III alone sold over 10 million copies by 2020, making it Bandai Namco's fastest-selling game until Elden Ring surpassed that record in 2022.
Bonfires are checkpoints that restore the player's health and resources when used, but also respawn most enemies in the area. Players reappear at the last bonfire they rested at after dying, and must retrieve their dropped souls from the point of death without dying again.
The series consists of three main games: Dark Souls (2011), Dark Souls II (2014), and Dark Souls III (2016). Each received expanded editions with downloadable content, and the first game was remastered in May 2018.
The Soulslike subgenre refers to games that share the core mechanics of the Dark Souls series, including its approach to difficulty, death, and environmental storytelling. The genre grew from the influence Dark Souls had on other developers, and FromSoftware's own related titles, including Bloodborne, Sekiro: Shadows Die Twice, and Elden Ring, are grouped under the related label Soulsborne.
Dark Souls integrates online play into its single-player experience through asynchronous mechanics. Players can see other players as ghosts, read messages left on the ground, and find bloodstains that replay how another player died. Direct cooperative and competitive play is possible through summoning and invasion, and covenants allow players to align with in-game factions for deeper multiplayer involvement.