Use ↑↓ for the right paddle, and WS for the left paddle. You get a point for every goal you hit past the other player. The first player to 11 points wins.
Pong is from many classic 90's video game consoles, like the Atari Flashback 2. (The ball may end up glitching and turning randomly by your paddle, but soon the ball should bounce back after a sec)
