Space Invaders came out in 1978 and effectively created the video game industry as a mass business. It was so popular in Japan that it caused a widely reported shortage of 100-yen coins, which remains the most impressive statistic in arcade history.

Tomohiro Nishikado had to build his own hardware to run it, and a limitation became the defining feature: as you destroy aliens, the game has fewer sprites to draw, so the remaining ones move faster. That accelerating panic was an accident of processing power and it's the best thing about the game.

The alien designs are among the most reproduced images in computing. Three rows of simple pixel shapes, legible at any size, and now recognised by people who have never played the game - they turn up as street art, tattoos and tile mosaics worldwide.

The two-tone descending bassline did the same job for sound.

This collection covers the invaders, the cannon and the shields, in their original pixel form.