Before silicon chips, computing relied on fragile, heat-generating glass bulbs. These vacuum tubes acted as switches and amplifiers, powering the colossal machines that filled entire rooms. They were temperamental and power-hungry, yet they marked the pivotal shift from mechanical calculation to electronic processing.

Data storage in its most tactile form. Stiff paper cards with perforated holes held the instructions for the world's most powerful machines. A dropped stack could mean days of reordering code. This medium dominated data processing for nearly a century, from the 1890 census to the mainframe era.

In high-security bunkers and converted mansions, early computers like Colossus were built not for commerce, but for survival. These room-sized machines broke unbreakable codes, shortening global conflicts and proving that information could be a weapon more powerful than artillery.