Mr White was an Artificial Intelligance (AI) which was a possesion of Ruby White. Mr White's name was suggested by Rani, following Ruby's last name and his simalarity with Mr Smith. (SJA: Goodbye, Sarah Jane Smith)
Appearance
Mr White was a pocket sized, white oval device with a blue screen.
Personality
Mr. White presented himself as friendly and affable, quickly making friends with Sarah Jane Smith's computer, Mr Smith.
History
Ruby White brought Mr. White with her when she assisted Sarah Jane and her group against the Dark Horde. She claimed to dredged the computer out of a swamp. It was Rani Chandra who suggested calling the computer "Mr White".
It was later revealed that Mr White was of Katesh origin, just like Ruby, who had created him rather then pulled him out of a swamp. (SJA: Goodbye, Sarah Jane Smith)