Japanese company Taito had the inspired idea around 1978 that killing aliens was extremely good fun.  So they invented a game called Space Invaders. The rest is history. It's a simple game with simple graphics, but it has one of the most vital assets for any computer game: gameplay.  Modern games seem to forget this with their fancy "3D graphics" and "millions of dollars".  All you need is a pointy green thing which shoots white stuff at a rampaging invasion of wobbling blobs.

Let me take you back... back to a world before pixels.  In those days, all people had were lines.  A company called Atari had recently wowed crowds with their clever use of lines in a game called Pong, but now this line technology had advanced.  It was 1979, and lines could be made to look like spaceships and big rocks and flying saucers... as long as you squinted a little. And so, Asteroids was born.

Frogger is a 1981 arcade game produced by Sega, developed by Konami. The game is regarded as a classic and was very popular for its novel gameplay and theme. It is one of the few classic arcade games whose gameplay did not involve killing hordes of enemies. Frogger is regarded as one of the "Top 100 Video games" of all time

Pac-Man is an arcade game developed by Namco and licensed for distribution by Midway that was first released in 1980. Immensely popular from its first release through today, Pac-Man is universally considered one of the classics of the medium, virtually synonymous with video games, and an icon of 1980s popular culture. This non-violent game appealed to both boys and girls.