The Mangekyou Sharingan is the evolved form of the regular Sharingan. An Uchiha rarely awakens this power. Only 9 Cannon people have managed to awaken the Mangekyou Sharingan. There are others who exist only in the anime, and are hence not included.
Here are all 9 Mangekyō Sharingan users in Naruto.
9. Danzo Shimura
Danzo is one of the few Non-Uchiha to wield a Mangekyou Sharingan. He stole Shisui’s eye, which led to the latter committing suicide. Danzo was able to use Shisui’s Mangekyō Sharingan ability Kotoamatsukami several times in a day. This process was sped up with the help of Hashirama’s cells.
8. Kakashi Hatake
Kakashi Hatake received the Sharingan from Obito Uchiha. He managed to awaken the Mangekyou Sharingan at the event of Rin’s death from his own hands. Kakashi didn’t know how to use the Mangekyō Sharingan for a long time. He learnt to control it sometime during the 3 year time skip.