About Dragon Ball

Origins of the manga
The Dragon Ball story takes place on Earth where Goku goes on adventures to find the Dragon Balls, as well as aspiring to become a great fighter, and compete in multiple martial arts tournaments. Goku later stops the evil Red Ribbon Army, then 3 years later, thwarts the Grand Demon King Piccolo's plans for world conquest, afterwards he and his friends protect the Earth from the Saiyan invasion. The setting also goes to Planet Namek later on in the series for Bulma, Gohan, and Kuririn to revive Goku's fallen friends from the Saiyan's attack, where they encounter Vegeta's higher ups, as well as the cosmic emperor, Freeza.

The Dragon Ball franchise is set in a multiverse[2]  composed of twelve[N 1]  numbered universes, each ruled by a number of benevolent and malevolent deities, respectively called Supreme Kais and Gods of Destruction. Almost all of the Dragon Ball series, except for parts of Dragon Ball Super, takes place in Universe 7. Years in the timeline are called "Ages", with most of the story occurring between Age 749 and Age 790.

Universe 7 contains several planets, including a fictionalized Earth, where humans reside, and Planet Vegeta, the home world of the Saiyans, a powerful and destructive race. Many other races also inhabit Universe 7, including Angels, Demons, Androids, Tuffles and Namekians. Humans are among the weakest races in the universe. The protagonist Goku is raised as a human on Earth but finds out that he is actually a Saiyan from Planet Vegeta.

Dr. Slump, an earlier manga series by Akira Toriyama, is set in the same multiverse.