Think of the transistor as the grain of sand at the core of the Silicon Valley pearl. The next layer of the pearl appeared when people strung together transistors, along with other discrete electronic components like resistors and capacitors, to make an entire electronic circuit on a single slice of silicon. This new device was called a microchip. Then someone came up with a specialized microchip that could be programmed: the microprocessor. The first pocket calculators were built around these microprocessors. Then someone figured out that it was possible to combine a microprocessor with other components and a screen — that was a computer. People wrote code for those computers to serve as operating systems and software on top of those systems. At some point people began connecting these computers to each other: networking. Then people realized it should be possible to “virtualize” these computers and store their contents off-site in a “cloud,” and it was also possible to search across the information stored in multiple computers. Then the networked computer was shrunk — keeping the key components of screen, keyboard, and pointing device (today a finger) — to build tablets and palm-sized machines called smart phones. Then people began writing apps for those mobile devices … .