History of Computers

• A computer is an electronic machine that processes data according to instructions and provides new information as output.

First Computer Programmer

• Agusta Ada Byron suggested using the binary system for Babbage's Analytical Engine in 1840 and wrote the first programs for it.

Early Computing Devices

• Tally Sticks: Early tools for recording numbers and quantities
• Abacus: A mechanical device for arithmetic calculations, invented in 2400 BC.
• Napier’s Bones: Invented by John Napier in 1614 to allow multiplication and division.
• Slide Rule: Created in 1622 by William Oughtred for multiplication, division, roots, and trigonometry.
• Pascaline: A mechanical calculator invented in 1642 by Blaise Pascal for basic arithmetic.
• Stepped Reckoner: Invented in 1672 by Gottfried Wilhelm Leibniz, capable of addition, subtraction, multiplication, and division.
• Jacquard Loom: Invented in 1881 by Joseph Marie Jacquard, used punched cards to automate textile production.

Mechanical Calculators and Early Computers

• Arithmometer: The first reliable mechanical calculator, invented by Thomas de Colmar in 1820.
• Difference Engine & Analytical Engine: Early mechanical computers created by Charles Babbage in 1822 and 1834.
• Scheutzian Calculation Engine: The first printing calculator, based on Babbage’s work, invented in 1843 by Per Georg Scheutz.
• Tabulating Machine: Invented by Herman Hollerith in 1890, used for summarizing data.
• Harvard Mark I: Also known as the IBM Automatic Sequence Controlled Calculator (ASCC), created by Howard Aiken.
• Z1: The first programmable computer, created by Konrad Zuse from 1936-1938.
• Atanasoff-Berry Computer (ABC): The first electronic digital computer, invented by John Atanasoff and Clifford Berry in the early 1940s.

Modern Computers and Development

• ENIAC: The first electronic general-purpose computer, completed in 1946 by John Presper Eckert and John Mauchly.
• UNIVAC 1: The first commercial computer, also developed by Eckert and Mauchly.
• EDVAC: The first stored-program computer, designed by John von Neumann in 1952.
• OSBORNE 1: The first portable computer, released in 1981.
• First Computer Company: The Electronic Controls Company, founded in 1949 by Eckert and Mauchly.

Computer Generations

• First Generation (1946-1958): Used vacuum tubes and machine language, limited to solving one problem at a time.
• Second Generation (1959-1964): Replaced vacuum tubes with transistors, making computers smaller, faster, and more reliable.
• Third Generation (1965-1970): Integrated circuits replaced transistors, increasing speed and reducing costs.
• Fourth Generation (1971-Present): Introduced microprocessors with many integrated circuits on a single chip, leading to personal computers and the Internet.
• Fifth Generation (Present to Future): Focus on Artificial Intelligence (AI), parallel processing, and superconductors.

Key Computer Concepts

• Computer Literacy: The ability to understand computer concepts, limitations, and effective usage.
• Information Processing Cycle: Input (data entry), Process (data processing), Output (result provision), Storage (for future use), Communication (data sharing).

Advantages of Computers

• Speed: Process data faster than humans.
• Repetitiveness: Perform the same task repeatedly without error.
• Accuracy: Give accurate results with correct input.
• Store and Retrieve Information: Store large amounts of data and retrieve it quickly.
• Logic Operations: Perform operations based on logical reasoning.
• Self-Operating: Execute tasks without human intervention once programmed.

Disadvantages of Computers

• Cannot correct wrong instructions.
• Prone to machine failure.
• Cannot interpret unstructured or ambiguous input like humans.

Elements of the Computing Process

• Hardware: Physical devices like monitors, keyboards, and printers.
• Software: Programs that activate hardware and process data.
• Data: Information processed by the computer.
• People: Users who input data and use the computer’s output.
• Procedures: Steps followed to complete tasks.
• Connectivity: Communication between computer systems.

Uses of Computers

• Information Systems/Data Processing
• Personal Computing
• Science Research & Engineering
• Education & References
• Computer-Aided Design (CAD)
• Artificial Intelligence
• Process/Device Control
• Entertainment
• Communication

Computer Applications in Society

• Education: Online learning, digital resources.
• Finance: Banking, stock trading.
• Government: Public services, e-governance.
• Healthcare: Medical records, diagnostic tools.
• Science: Data analysis, simulations.
• Publishing: Digital media, online content.
• Travel: Booking systems, logistics.
• Manufacturing: Automation, process control.
• Business & Research: Data management, innovation, and analysis.

Basic Computer Architecture Overview

• History of Computers: Evolution from early mechanical devices like the abacus to sophisticated modern machines.
• Introduction to Arduino: A microcontroller-based platform for learning and prototyping embedded systems and electronics.

Key Components of a Computer System

• Input/Output Units: Devices like keyboards, monitors, and printers.
• Memory/Storage Units: Memory (RAM) is temporary, while storage (hard drives or SSDs) is permanent.
• Central Processing Unit (CPU): Executes instructions from programs.

Motherboard and Bus Architecture

• Motherboard Components:
  • Northbridge: Connects the CPU to high-speed components.
  • Southbridge: Handles slower, peripheral components.
  • Bus: Communication system connecting various computer components.
• Northbridge and Southbridge Communication:
  • The CPU connects to the Northbridge for memory and graphics.
  • The Southbridge manages slower tasks like I/O operations.

CPU Architecture: von Neumann vs. Harvard

• von Neumann Architecture: The CPU fetches instructions and data from the same memory space.
• Harvard Architecture: Uses separate memory for instructions and data, improving speed.

Components of the CPU

• Arithmetic Logic Unit (ALU): Performs arithmetic and logical operations.
• Control Unit (CU): Manages instruction execution and issues commands to the ALU; includes the Memory Management Unit (MMU) and I/O Interface.
• Registers in the CPU: Small, fast storage locations that include the Program Counter (PC), Instruction Register (IR), and Status Register.

Memory and Data Operations

• Memory Operations:
  • Memory Address Register (MAR): Holds the address to fetch/store data.
  • Memory Data Register (MDR): Holds data being read/written.
• Data Transfer: Occurs between the MDR and memory.
• Memory Capacity: Determined by the MAR width; insufficient memory impacts system performance.

Types of Memory

• RAM (Random Access Memory):
  • DRAM: Cheap, requires frequent refreshing.
  • SRAM: Faster, more expensive, used in caches.
• ROM (Read-Only Memory):
  • Non-volatile (e.g., BIOS).
  • Flash ROM: Used in modern systems for storage like BIOS.
• CMOS Memory: Low-power, small, fast memory for system settings and BIOS storage.

Cache Memory and Levels

• Cache Levels:
  • L1 Cache: Smallest, fastest, closest to the CPU.
  • L2 Cache: Slower, larger than L1, stores frequently used data for quick access.

Machine Cycle

• Fetch-Decode-Execute-Store Cycle:
  • Fetch: Retrieves an instruction.
  • Decode: Decodes the instruction.
  • Execute: Executes the instruction.
  • Store: Stores the result back in memory.

ACM Code of Ethics and Professional Conduct

• The ACM Code of Ethics guides computing professionals on ethical behavior, emphasizing the societal impact of their actions and the public's best interest.
• The Code includes:
  • General Ethical Principles
  • Professional Responsibilities
  • Professional Leadership Principles
  • Compliance with the Code

General Ethical Principles

• Computing professionals should:
  • Contribute to society and human well-being.
  • Avoid harm.
  • Be honest and trustworthy.
  • Be fair and equitable.
  • Respect work and ideas.
  • Respect privacy.
  • Honor confidentiality.

Professional Responsibilities

• Computing professionals should:
  • Achieve high quality.
  • Maintain professional competence.
  • Respect rules.
  • Accept and provide professional review.
  • Evaluate computer systems' impacts.
  • Foster public understanding.
  • Ensure authorization.
  • Design secure systems.

Professional Leadership Principles

• Leaders in computing should:
  • Prioritize public good.
  • Promote social responsibility.
  • Enhance the quality of work life.
  • Support professional growth.
  • Manage systems carefully.

Compliance with the Code

• Computing professionals should:
  • Uphold the Code.
  • Treat violations seriously.

Computer Ethics

• Computer Ethics: Moral principles related to computing practices.
• Ten Commandments of Computer Ethics: Actionable ethical guidelines, including not harming others, interfering with their work, or stealing.

Responsibilities of Computing Professionals

• High level of responsibility toward clients, employers, colleagues, and the public:
  • Responsibilities to Clients and Users:
    • Perform tasks competently and ethically.
    • Consider the social effects of computing on stakeholders.
  • Responsibilities to Employers:
    • Maintain confidentiality and respect intellectual property.
    • Use proprietary resources for the employer's benefit.
  • Responsibilities to Other Professionals:
    • Demonstrate collegiality and mutual respect.
    • Participate in peer review and mentor junior professionals.
  • Responsibilities to the Public:
    • Prioritize public safety, health, and welfare.
    • Consider whistle-blowing in cases of serious public safety threats.

Additional Ethical Guidelines

• Various societies provide ethical guidelines that align with the ACM Code.
  • Australian Computer Society (ACS): Ethical behavior and public trust.
  • IEEE Code of Ethics: Safety, honesty, and fairness.
  • British Computer Society (BCS): Competence and ethical practice.
  • IEEE, ITA, LOPSA: Codes to foster professionalism and ethical decision-making.

Ethics in Specialized Areas

• Includes:
  • Internet, Cyber, E-Commerce, Web, Business Computer, and Consumer Computer Ethics.

Professional Ethics

• Professionals must follow a set of ethical norms and values:
  • Competence: Work done to the best of their ability.
  • Confidentiality: Safeguard sensitive information.
  • Public Welfare: Consider the broader impact of their work, especially concerning public health and safety.