Introduction to Computer Science - Chapter 1

Introduction to Computer Science

• Course taught by Dr. Ahmed Taha
• Offered by the Computer Science Department, Faculty of Computers & Artificial Intelligence, Benha University

Book Details

• Book Title: New Perspectives on Computer Concepts, 2016, Comprehensive
• Authors: June Jamrich Parsons, Dan Oja
• Publisher: Cengage Learning
• Edition: 18th Edition (June 22, 2015)

Book Contents

• Computers and Digital Basics (Chapter 1)
• Computer Hardware (Chapter 2)
• Computer Software (Chapter 3)
• Operating Systems and File Management (Chapter 4)
• Local Area Networks (Chapter 5)
• The Internet (Chapter 6)
• The Web and E-mail (Chapter 7)
• Digital Media (Chapter 8)
• The Computer Industry: History, Careers, and Ethics (Chapter 9)
• Information Systems Analysis and Design (Chapter 10)
• Databases (Chapter 11)
• Computer Programming (Chapter 12)

Contents of Chapter One: Computers and Digital Basics

• All Things Digital
• Digital Devices
• Digital Data Representation
• Digital Processing

The Digital Revolution

• Ongoing process of social, political, and economic change via digital technology (computers and the internet)
• Information Age: A period where information is easily accessible, significantly impacting daily life (from economy to social relations)
• Digitization: The process of converting text, numbers, sound, photos, and video into data for processing by digital devices. This allows diverse data types to be represented as a common set of signals, eliminating the need for separate devices.
• Beginning of the Digital Revolution:
  • World War II (1939–1945): First digital computers used for code-breaking and missile trajectory calculations
  • 1950s: Marketing of computers for business applications (payroll, inventory)
  • 1980s: Generally considered the start of the digital revolution.

The Digital Revolution Phases

• Data Processing: Early computers were very large and expensive, primarily used within corporations and government agencies.
• Personal Computing: Personal computers emerged in the 1970s, with applications like word processing and gaming dominating usage, though graphics and sound capabilities were still basic.
• Network Computing: Computers became networked, and the internet and web technologies allowed computers to be connected for sharing data and communications in a widespread way (1995-2010).
• Cloud Computing: Storing and using data/applications online (accessible via internet), rather than locally on a computer. Applications were more widespread on digital devices and mobile devices.

Phase I: Data Processing

• Data processing is the original computing model for the digital revolution.

Phase II: Personal Computing

• First personal computers created in 1976
• Popular uses were word processing and gaming; sound and graphics were primitive.

Phase III: Network Computing

• Computer Network: Linked computers for sharing data and resources.
• The Internet: A global network originally developed for military purposes.
• The Web: Linked documents, graphics, and sounds accessible over the internet.

Phase IV: Cloud Computing

• Cloud represents internet-based services (applications, social media) available from computers and handheld devices
• Social media: Cloud-based apps for social interaction (social networking, wikis, blogging, photo sharing, and microblogging sites).

Computer Basics

• Computer: A multipurpose device accepting input, processing data, storing data, and producing output via a computer program.
• Input: Data entered into the computer system (typed, submitted, transmitted).
• Output: Result produced by a computer
• Data: Symbols representing raw facts (objects, and ideas).
• Information: Processed, structured, data presented usefully.
• Memory: Temporarily stores data awaiting processing or output.
• Storage: Stores data permanently.
• File: A named collection of data in a storage medium (hard drive, CD, flash card).
• Computer Program: A series of instructions telling a computer how to handle processing tasks, forming computer software.
• Application Software: Computer programs for specific tasks (word processing).
• System Software: Enables the computer system to function efficiently (operating system).
• Computer Types:
  • Personal computers: Designed for individual use; typically include keyboard and screen
  • Workstation: Ordinary personal computer connected to a network or high-performance desktop for special tasks (graphics, medical imaging)
  • Servers: Support computers on a network (i.e., Internet, home network), supply data to clients, can be any type of computer configured as a server
  • Mainframes: Large, expensive computer that simultaneously processes data for numerous users.
  • Supercomputers: The world's fastest computers, used for complex calculations (weather forecasting, code breaking).
• Microcontroller: Built-in special-purpose microprocessor in a machine it controls (microwave, digital video recorder).

Data Representation Basics

• Data Representation: Form in which data is stored, processed, and transmitted.
• Data types: Digital (text, numbers, graphics) / Analog (infinite scale values)
• Binary digits (bits, 0s and 1s) are used for representing digital data.
• Character data: Letters, symbols, numerals (not arithmetic operations).
• Codes (ASCII, EBCDIC, Unicode) represent character data
• Images: Digitized by treating as colored dots, each is assigned a binary number based on color.
• Sound: Analog waveforms are digitized through sampling.

Quantifying Bits and Bytes

• Bit: One binary digit
• Byte: 8 bits
• Kilobit/Kilobyte, Megabit/Megabyte, Gigabit/Gigabyte etc are larger units of measurement.

Circuits and Chips

• Bits in electronic circuits: Represented as two states (ON/OFF).
• Integrated Circuit (IC): Super-thin semiconductor slices with microscopic circuit elements (transistors, capacitors, logic gates), usually packaged inside a protective carrier.
• System board: houses computer components (providing interconnections).

Programs and Instruction sets

• Computer programmers design programs controlling digital devices.
• Programming languages: (C, BASIC, COBOL, Java). Employ command words for actions (Print, Get, If).
• Conversion from high-level programming language to machine language. Compiler / Interpreter converting the high-level code into machine language.

How does source code get converted?

• Programmers create high-level instructions in source code.
• A compiler or interpreter converts source code to executable machine code.
• Machine code: Sequences of 0s and 1s representing processor instructions.
• Op code: Command word for an operation (add, compare, jump).
• Operand: Specifies data/address for an operation (within a given instruction).

What happens inside a computing chip?

• ALU (Arithmetic Logic Unit): Performs arithmetic and logical operations (adding/subtracting/comparison).
• Control Unit: Fetches instructions, loads data into registers, coordinates processing initiation.

Instruction Cycle

• Instruction cycle: Process where a computer executes an instruction (fetch, interpret, and execute commands).
• Stages include fetching the instruction, decoding it to understand its purpose, performing the operation, and updating the instruction pointer.

This quiz covers the fundamental concepts of Chapter 1 from the book 'New Perspectives on Computer Concepts'. It focuses on digital basics, including digital devices and data representation. Test your understanding of essential digital terminology and concepts.