| Generation | Years | Main technology | Size & power | Speed | Languages / Software | Examples |
|---|---|---|---|---|---|---|
| 1st | 1940–1956 | Vacuum tubes; magnetic drum memory; punched cards | Room-sized; 10–150 kW; huge heat; tonnes | milliseconds (10⁻³ s), ~1,000–5,000 ops/s | Machine language (binary) | ENIAC, EDVAC, UNIVAC I, IBM 701, IBM 650 |
| 2nd | 1956–1963 | Transistors; magnetic core memory; tape | Cupboard-sized; a few kW; less heat | microseconds (10⁻⁶ s), ~10⁵ ops/s | Assembly, FORTRAN, COBOL, ALGOL; batch OS | IBM 1401, IBM 7090, CDC 1604, UNIVAC 1108, PDP-1 |
| 3rd | 1964–1971 | Integrated Circuits (SSI/MSI); keyboards & monitors; disks | Desk-sized minicomputers; hundreds of W | nanoseconds (10⁻⁹ s), ~10⁶–10⁷ ops/s | High-level languages (BASIC, Pascal, C); multiprogramming, time-sharing OS | IBM System/360, PDP-8, PDP-11, Honeywell 6000 |
| 4th | 1971–present | Microprocessor (LSI → VLSI → ULSI); semiconductor RAM; GUI; networks & internet | Desktop → laptop → phone → watch; 5–500 W | picoseconds (10⁻¹² s), 10⁹–10¹² ops/s | C++, Java, Python; Windows, macOS, Linux, Android, iOS | Intel 4004, Altair 8800, Apple II, IBM PC, Macintosh, Pentium, Core i9, Ryzen, Apple M4 |
| 5th | Present → future | AI, parallel processing, GPUs/NPUs/TPUs, quantum & neuromorphic chips, nanotechnology | Cloud data centres (MW) + tiny edge devices (mW) | exaFLOPS (10¹⁸) in supercomputers; TOPS in phones | Natural language (prompting), ML frameworks, LLMs (GPT, Gemini, Claude) | Frontier, El Capitan, Nvidia Blackwell, Google Willow, ChatGPT, Copilot+ PCs, robots |
- ISwitching device shrank: vacuum tube (size of a bulb, ~2 W each) → transistor (pea-sized) → IC (thousands per chip) → VLSI (millions) → today 3 nm transistors (about 15 silicon atoms wide).
- IIMemory: magnetic drum → magnetic core → semiconductor RAM → DDR5 (up to 8,400 MT/s) → HBM3e for AI.
- IIIInput/Output: punched cards & plugboards → teletype → keyboard + CRT → mouse + GUI → touch → voice → gesture/brain interface.
- IVCost per calculation has fallen by more than a trillion times since 1946.
// Keep exploring
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