Sto was a planet inhabited by a humanoid species outwardly identical to humans, although other species, such as the Zocci, were represented in the planet's population. Bannakaffalatta was, for example, a resident of Sto — as were most of the passengers and crew onboard a version of the Titanic the Tenth Doctor once encountered.
At least one of the planet's indigenous races, at some point in the past, apparently worshipped a god named Vot.
Stovian society was rather similar to the terrestrial, including unemployment and television shows. The inhabitants of Sto had also an interest in Earth history and culture, given the popularity of the Titanic recreation, although some Sto residents developed a somewhat skewed view of Earth history and customs (such as Mr Copper's take on Christmas).
Cyborgs and androids were generally discriminated against by the dominant culture of the planet. (TV: Voyage of the Damned) When the Twelfth Doctor found himself sent back to Sto in 1917, after being touched by a Weeping Angel, he quickly joined the civil rights movement and eventually became its leader. Using the wealth and influence he gained, he organised an underground railroad that smuggled cyborgs off-world. The Doctor eventually got a job at Max Capricorn Cruiseliners, naming the starship Titanic that his earlier self would encounter. Thanks to the Doctor, (COMIC: A Confusion of Angels) laws were passed in the early 21st century allowing cyborgs more freedoms, including the right to marry.
Cyborg Caravans was a travelling society on Sto. (TV: Voyage of the Damned) In 2017, the Twelfth Doctor left Sto and reunited with Bill Potts and Nardole, only minutes after he'd been touched from their perspective. (COMIC: A Confusion of Angels)
During the Last Great Time War, the Eighth Doctor and Bliss went travelling there where they were met by the Twelve and Doctor Ogron. (AUDIO: Planet of the Ogrons)
Known inhabitants of Sto included Astrid Peth, Mr Copper, Alonso Frame, Bannakaffalatta, Foon Van Hoff, Morvin Van Hoff, Rickston Slade, Max Capricorn, Captain Hardaker, the Titanic's Chief Steward, the Titanic's Engineer, the Titanic's Kitchen Hand and a singer. (TV: Voyage of the Damned)