IB Digital Society 3.3D Evolution of Computing Notes

3.3D Evolution of Computing

The long arc of computing

1. The first electronic computers (1940s) filled entire rooms, cost a fortune and were owned by governments and universities; within a lifetime that power shrank to fit a pocket and became cheap enough for billions to own.
2. The whole story runs on one force: miniaturisation. As the switching parts got smaller, computers got faster and cheaper and used less power.
3. Historians split the arc into generations, each defined by its switching component. Each newer generation used a smaller switching component than the one before.

The generations of hardware

1. The first generation ran on vacuum tubes, glass valves the size of a lightbulb acting as switches: bulky, hot and failure-prone, making machines enormous and unreliable.
2. The breakthrough was the transistor, a tiny solid switch using far less power; then the integrated circuit (many transistors on one slice of silicon); then the microprocessor (a whole processor on one chip).
3. Each generation did the same job with a smaller, cheaper, more reliable part: a modern fingernail-sized chip holds billions of switches that once filled a building.
   1. The integrated circuit was the pivotal leap: etching transistors together let manufacturers mass-produce complex circuits cheaply, which is why computing could be made in large quantities at low cost.

Moore's Law

1. In 1965 Gordon Moore (Intel co-founder) noticed the number of transistors on a chip was doubling about every two years and predicted it would continue: this is Moore's Law.
2. Repeated doubling is exponential growth: computing power becomes many times greater within a decade, which is why a phone outclasses a room-sized machine of the past.
3. Contested: Moore's Law is really an observation rather than a fixed rule, and it is now slowing as transistors shrink toward atom-scale physical limits, so speed-ups no longer come automatically with each new chip.

What the growth made possible

1. Cheaper, more powerful chips let computing escape the laboratory, which makes this a social story as much as a technical one. The microprocessor made the personal computer possible, and the smartphone later put a powerful computer in billions of hands.
2. Cheap, abundant computing is the foundation almost everything digital rests on: the internet, social media, streaming, online banking and mobile apps became practical only once hardware was small and cheap.
3. Each wave reshaped society: mainframes served institutions, the personal computer reached homes, the internet connected them, the smartphone made it mobile and always-on. In each case the change in hardware came before the change in how people used computers.

Emerging frontiers: AI and quantum

1. As gains from shrinking transistors fade, one direction is artificial intelligence (sometimes called a fifth generation): the focus shifts from raw speed to machines that learn patterns, recognise speech and images, and make predictions.
2. Another frontier is quantum computing: instead of bits that are 0 or 1, it uses qubits that can blend 0 and 1 at once (superposition), exploring many possibilities together.
3. Quantum could one day crack problems that defeat today's machines, such as drug design or breaking encryption. Contested: for now it stays experimental, fragile and suited only to particular problems, so treat it as a promising frontier rather than a general replacement, and check claims about it against what the hardware can actually do.
   1. AI is the most visible wave now: the surge of generative AI shows how a shift in what computers can do (not just how fast) can reshape work and creativity almost overnight.

Evolution, power and its limits

1. The benefits spread unevenly and came with costs. A new phone reaches some pockets every year while others still lack reliable access, and discarding working devices drives rising electronic waste.
2. Who steers evolution? Chip design and frontier AI and quantum work sit with a few wealthy companies and countries, concentrating the power to shape the next stage of digital society in very few hands.