A strange little side quest
A quick detour while Snap the Shape: Japan waits for your next move: The name Tetris combines a reference to four-square pieces with Pajitnov's interest in tennis. That old idea kept changing rather than disappearing. In 1958, Tennis for Two used an analog computer and an oscilloscope to turn simple physics into a playable tennis-like demonstration. That history is one reason familiar mechanics can still feel new when they are recombined well.