How did transistors improve the speed and reliability of digital computers?

Transistors revolutionized digital computers by replacing vacuum tubes, which were the primary active logic elements in early machines. This transition significantly improved both speed and reliability through several key physical advantages:12

• Miniaturization and Density: Transistors are inherently small, allowing engineers to pack a vast number of them into a limited space. This high density is essential for complex logic applications and eventually enabled the development of integrated circuits containing millions of components.13
• Efficiency and Heat Management: Unlike vacuum tubes, which generated excessive heat, transistors operate with low power consumption. This reduction in heat generation prevented the thermal issues that limited the performance and longevity of earlier, tube-based systems.142
• Switching Speed: Transistors function as high-speed switches that represent the binary 1s and 0s of digital computing. By achieving low propagation delays, they allowed for much faster processing speeds than vacuum tubes. Modern transistors can perform at speeds exceeding 100 billion on-and-off cycles per second.31
• Reliability: The transistor’s solid-state nature provided far greater operational reliability compared to the fragile and short-lived vacuum tubes.24