Comprehensive Study Notes: History of Computing & Basic Computer Concepts

Pre-Mechanical Age (5000 BC – 1450 AD)

• Communication Media & Symbols

  • Petroglyphs / Pictographs – simple figures carved into rock.
  • Geometric signs: dots, squares, etc.
  • Ideographs: symbols representing complete ideas.
  • Cave paintings: earliest visual story-telling.
  • Shift from images → symbols for sounds (birth of phonetic writing).
  • $(3100\,\text{BC})$ Mesopotamia: Cuneiform – first full written language.
  • Phoenicians: alphabet of single consonants & syllables.
  • Greeks: added vowels to Phoenician set.
  • Romans: assigned Latin names → basis of modern Western alphabet.

• Input Technology – Paper & Pens

  • Sumerians: clay tablets + stylus scratches.
  • $(2600\,\text{BC})$ Egypt: Papyrus → first true "paper".
  • $(100\,\text{AD})$ China: rag-based paper manufacturing.

• Output Technology – Books & Libraries

  • $(600\,\text{BC})$ Greeks: folded papyrus leaves → bound scrolls.

• Numbering Systems

  • $1{-}9$ = vertical strokes.
  • $10$ = heel-shaped / circular hieroglyph.
  • $100$ = coiled rope.
  • $1000$ = lotus blossom.
  • $(875\,\text{AD})$ Formal concept of $0$.

• First Calculator – Abacus

  • Invented $(\approx500\,\text{BC})$ in Babylonia; popularized in India.
  • Performs addition & subtraction via bead positions.

Mechanical Age (1450 – 1840)

• 1450 – Gutenberg’s Movable Metal-Type Press → first "information explosion".

• Early Mechanical / General-Purpose “Computers”

  • $1614$ John Napier: Logarithms – convert $\times / \div$ into $+/-$.
  • $1617$ Napier: "Arabian Lattice" multiplication aid.
  • $1623$ Wilhelm Shickard: 6-digit gear-based mechanical calculator.
  • $1625$ William Oughtred: Slide Rule (cursor window) → roots, logs, trig.
  • $1642$ Blaise Pascal: Pascaline – wheel-and-gear adder.
  • $1671$ Gottfried Leibniz: Stepped Reckoner – multiplies 5-digit × 12-digit.
  • $1801$ Joseph Marie Jacquard: automated loom; punched cards = first program medium.
  • $1820$ Charles X. Thomas de Colmar: Arithmometer – commercial calculator.
  • $1821$ Charles Babbage: Difference Engine (polynomial tables).
  • Later Analytical Engine – punch-card-controlled, conditional branching; regarded as first design for a programmable, "thinking" machine.
  • Ada Augusta Lovelace – wrote algorithms for it → first computer programmer; namesake of the ADA language.

Electro-Mechanical Age (1840 – 1940)

• Harnessing Electricity

  • $1800$ Alessandro Volta: Voltaic Pile – first chemical battery (zinc + copper discs in brine-soaked felt).

• Telecommunications Milestones

  • Telegraph – long-distance text via Morse Code.
  • $1876$ Alexander Graham Bell: Telephone ("Watson, come here…"; 1877 Philly Expo).
  • $1894$ Guglielmo Marconi: proved radio waves span space → wireless telegraphy.

• Foundations of Logical Computing

  • $1852$ George Boole: Boolean Algebra (binary logic).

• Mechanical/Electromechanical Calculators

  • $1853$ Pehr & Edvard Scheutz: Tabulating Machine – 15-digit input, rounds to 8, prints.
  • $1885$ Dorr Felt: Comptometer (key-driven adder).
  • $1889$ Felt’s Comptograph – adds built-in printer.

• Punched-Card Data Processing

  • $1890$ Herman Hollerith: census tabulation with punch cards.
  • Founded Tabulating Machine Co. → CTR → $1921$ renamed IBM.

• 1893 – Millionaire Calculator

  • Otto Shweiger (Swiss): first efficient 4-function geared calculator.

• 1906 – Vacuum Tube (Lee De Forest)

  • First electronic switch; glass bulb analogue of a relay.

Electronic Age (1941 – Present)

• Early Programmable Machines

  • $1941$ Konrad Zuse Z3 – electromechanical, program-controlled, engineering focus.
  • $1942$ John Atanasoff & Clifford Berry: ABC – first fully electronic digital computer.
  • $1944$ Howard Aiken: Harvard Mark I – first to store programs internally.

• Generations of Digital Computers

  • 1st Gen (1951–1958) – Vacuum tubes + resistors + metal wiring.
  • 2nd Gen (1959–1963) – Transistors replace tubes → smaller, faster, cooler.
  • 3rd Gen (1963–1974) – Integrated Circuits house multiple transistors on one chip.
  • 4th Gen (1979–Present) – Microprocessors (entire CPU on a single silicon die).

• History of Intel Microprocessors

  • $1971$ 4004 – 4-bit; powered Busicom calculator; birthed embedded intelligence.
  • $1972$ 8008 – 2× performance of 4004; used in Mark-8 hobby PCs.
  • $1974$ 8080 – heart of the first personal computers.
  • $1978$ 8086 / 8088 – foundation for IBM PC (8088 variant used).
  • $1982$ 80286 (286) – first with full upward software compatibility.
  • $1985$ 386 – $275{,}000$ transistors; 32-bit multitasking.
  • $1989$ 486 DX – on-chip math coprocessor; enabled GUI "point-and-click".
  • $1993$ Pentium® – processed real-world data (speech, sound, handwriting, images).
  • $1997$ Pentium® II – multimedia-centric; enhanced video/audio/graphics.
  • $1999$ Pentium® III – added $70$ Streaming SIMD (SSE) instructions; better 3D & media.
  • $2000$ Pentium® 4 – higher clock speeds; optimized for video editing, music encoding, multitasking, real-time comms.

Computer Hardware Fundamentals

• System Unit (Core Case) – processes, stores, and manages all major functions.

• Essential Internal Components

  • Power Supply – converts AC→DC; built-in cooling fan.
  • Motherboard – primary circuit board interconnecting all components.
  • CPU – central processing unit; "brain" executing instructions.
  • RAM – volatile, working memory for active data.
  • Expansion Slots – add-on cards (sound, network, GPU, etc.).
  • Hard Drive – mass storage (often Drive C:).
  • CD-ROM Drive – optical read-only media.
  • 3½-in Floppy Drive – legacy magnetic media I/O.
  • System Case / Chassis – protective enclosure.

• System-Case Form Factors

  • Desktop – low, horizontal; monitor often sits on top.
  • Tower – upright; smaller desk footprint, easier expansion.

Input & Output Devices

• Input Devices – feed data to computer.

  • Keyboard, Mouse, Microphone, Scanner, etc.

• Output Devices – convey processed information.

  • Monitor, Speakers, Printers.

• Printer Types & Traits

  • Laser – toner + laser imaging → fast, high-quality.
  • Inkjet / Bubble Jet – liquid ink; strong color capability.
  • Dot Matrix – impact pins + ribbon; good for carbon copies.
  • Classification axes: Quality of type, Speed, Impact vs. Non-Impact, Graphics support.

Computer Categories

• Microcomputer (Personal Computer) – single user; desktops & portables; mainstream since late 1970s.
• Minicomputer – mid-range; multi-user; less powerful than mainframe.
• Mainframe – large, robust; supports hundreds/thousands of users concurrently.
• Supercomputer – fastest, highest cost; scientific & mathematical modeling.

Core Conceptual Frameworks

• Three Fundamental Hardware Elements

  • System Unit
  • Input Devices
  • Output Devices

• Five Elements of the Computing Process

  1. Hardware – physical equipment (CPU, monitor, keyboard).
  2. Software – programs/instructions (OS, apps).
  3. Data – raw facts / information manipulated.
  4. People – end-users & IT professionals.
  5. Procedures – methods/rules (login, save, print, etc.).

Summary of Key Dates & Inventions (Chronological Quick-Ref)

• $5000\,\text{BC}$ Petroglyphs
• $3100\,\text{BC}$ Cuneiform
• $2600\,\text{BC}$ Papyrus
• $600\,\text{BC}$ Scrolls
• $500\,\text{BC}$ Abacus
• $1450$ Gutenberg Press
• $1614{-}1671$ Napier, Shickard, Oughtred, Pascal, Leibniz devices
• $1801$ Jacquard Punched-Card Loom
• $1821$ Babbage Difference/Analytical Engines
• $1840{-}1940$ Boolean algebra, Telegraph, Telephone, Radio, Vacuum Tube
• $1890$ Hollerith Census & IBM roots
• $1906$ Vacuum Tube → electronics era
• $1941{-}44$ Z3, ABC, Harvard Mark I
• $1951{-}$ Generational computer evolution (Vacuum → Transistor → IC → Microprocessor)
• $1971{-}2000$ Intel 4004 → Pentium 4