In what two decades did an  electronic, digital or computer device that outputs a video signal or visual image to display a video game that one or more people can play, become popular?
Early history of video games: The history of video games spans a period of time between the invention of the first electronic games and today, covering a long period of invention and changes. Early history of video games:  Video gaming would not reach mainstream popularity until the 1970s and 1980s, when arcade video games, gaming consoles and home computer games were introduced to the general public. Video game console: A video game console is an electronic, digital or computer device that outputs a video signal or visual image to display a video game that one or more people can play.
1970s and 1980s