Created by Josef Kates, Bertie the Brain is the first public display of an video game. The game was built for the 1950 Canadian National Exhibition in Toronto. The four meter (13 foot) tall computer allowed exhibition attendees to play a game of tic-tac-toe against an artificial intelligence. The player entered a move on a lit keypad in the form of a three-by-three grid, and the game played out on a grid of lights overhead. The machine had an adjustable difficulty level. After two weeks on display by Rogers Majestic, the machine was disassembled at the end of the exhibition and largely forgotten as a curiosity.