Introduction to Computer Science

Introduction to Computer Science

• Introduction to computer science by Dr/Safynaz AbdEl-Fattah Sayed, Computer Science, Beni-suef University.

What is a Computer?

• There's no single definition for a computer, but it can be described as an electronical device that takes input, processes data with mathematical and logical operations at high speeds with accuracy, stores data, and outputs the results when needed.
• Input: the data that a computer receives.
• Processing: the operations performed on the input data.
• Storage: the area where data is saved.
• Output: the processed results from the computer.

What is a Computer? - Example

• Example: Summation of two numbers (2, 5)
  • Input: User enters 2 and 5
  • Processing: The computer adds 2 and 5, arriving at 7
  • Output: The computer displays the result (7)
  • Storage: The computer saves the input data or output for future use.

Computer Characteristics

• Computers are made of interconnected parts that work as a single unit.
• Input units allow for the entry of data.
• Special instructions called computer software direct the computer to process data (mathematical & logical operations).
• Output units display processed information in multiple formats.
• Computers have high-capacity storage for data and information.
• Computers can communicate with other devices and form networks.

Table 1-1: Difference Between a Person and a Computer

Stages of Computer Development - Early Historical Stage

• Attempts to create machines that perform mathematical operations easier began around 2000BC.
• The Abacus, a counting machine invented in China, is a manual method for counting and calculation and is still used today to teach children math.

Stages of Computer Development - Mechanical and Electromechanical Stage

• 1643AD: Blaise Pascal invented a semi-automatic mechanical calculator for adding and subtracting decimal numbers.
• The machine used 8 metal disks with engraved decimals, each rotating at specific distances to add/subtract.
• 1944AD: Aiken and Grace Hopper, assisted by IBM, created the first computer (electromechanical calculator) called Mark-1.

Stages of Computer Development - Modern Computer Generations

• Computer development has many stages and generations reflecting continuous progress in design and accessories.
• Today's computers can be grouped into five computer generations, with each having unique characteristics and manufactured within specific time periods.

The Evolution of Computers

• First Generation (1940-1956): Vacuum tubes, large and expensive, produced massive heat. Early computer examples include UNIVAC.
• Second Generation (1956-1963): Transistors were used instead of vacuum tubes, making computers smaller, faster, and less energy-intensive.
• Third Generation (1964-1971): Integrated circuits (ICs) made from silicon wafers on computer chips—producing smaller, faster, and cheaper computers. Memory increased with these.
• Fourth Generation (1971-2012): Microprocessors (CPU placed on a single chip) made computers significantly smaller, faster, and cheaper. Personal computers and laptops appeared.
• Fifth Generation (Present & Beyond): High-capabilities, Multi-core processors, rapid speeds, and more mobile, portable smart devices are prominent characteristics of this generation. Artificial intelligence is present but in a developmental stage.

First Generation

• Vacuum tube computers
• High electricity use
• Large in physical size
• Heavy weight
• Enormous heat generated
• Exemplars: ENIAC, EDVAC, EDSAC, UNIVAC.

Second Generation

• Transistors as replacements for vacuum tubes
• Smaller in size
• Less heat produced
• Higher efficiency
• Started programming languages

Third Generation

• Integrated circuits
• Semiconductor devices are used extensively
• Reduced power consumption
• Increased speed and efficiency

Fourth Generation

• Microprocessor Technology
• Significant reduction in sizes compared to previous generations
• More powerful.
• More faster, efficient and affordable
• PC, laptops, and workstations emerged

Fifth Generation

• Extremely high speeds
• Artificial intelligence capabilities
• The most advanced technologies in computing
• Personal computers, laptops, mobile phones

Computers Classification

• Six types of computers:
  • Embedded computers
  • Mobile devices
  • Personal computers (PCs)
  • Midrange servers
  • Mainframe computers
  • Supercomputers

Embedded

• Designed for specific tasks within a larger product.
• Cannot be used as general purpose computers
• Examples: household appliances, thermostats, sewing machines, cars.

Mobile Devices

• Small devices with built-in computing/Internet capability.
• Usually based on cellular phones.
• Examples: smart phones, smart watches, handheld gaming devices, portable media players.

Midrange Servers

• Medium-sized computers used in small networks .
• Also known as minicomputers
• Usually located in out-of-the-way places and serve many users at once.
• Users can connect through different devices .

Mainframe Computers

• Powerful computers managing large amounts of centralized data for large organizations (hospitals, universities, businesses, banks, government offices).
• Located in climate-controlled data centers and connected to a network.
• More powerful than midrange servers.
• Operate 24/7.
• Can be referred to as high-end/enterprise-class servers.

Supercomputers

• Powerful, expensive, and the fastest type of computers.
• Generally run one program at a time.
• Commonly built by connecting smaller computers.
• Used in complex tasks such as space exploration, weather forecasting, scientific research.
• Example technology: Grid Computing

Personal Computers

• Designed for one user at a time.
• Least powerful; most widely used, and fastest-growing computer.
  • Types include: Desktop, Laptop (Notebook), Tablet, Smartphones, and Wearables

Personal Computer System Parts

• System unit: The case enclosing the main circuit boards, microprocessor, memory, power supply, storage devices..
• Display device: Consists of graphics card, GPU, and display screens/monitors.
• Keyboard: Primary input device.
• Mouse: Input device for manipulating on-screen objects.
• Hard disk drive: Primary storage device for personal computers.
• Optical drives: Use CDs, DVDs, etc. for storing data.
• Sound card and speakers: For sound output.
• Peripheral devices: Enhancing devices like printers, digital cameras, scanners, joysticks, graphics tablets

Data versus Information

• Data are raw, unprocessed facts (numbers, text, images, sound).
• Information is the result of processing data.
• Types of Data: Structured (relational databases), Semi-structured (documents, emails), Unstructured (HTML pages)
• Data File types: Documents, Worksheets, Databases, Presentations.

Components of Computers

• Hardware: Physical components of a computer.
• Software: Collection of programs that allow the computer to perform operations.

This quiz introduces the fundamental concepts of computer science, including the definition of a computer, its components, and characteristics. Participants will explore how computers process input, perform calculations, and produce output, alongside practical examples. Perfect for beginners seeking to understand the basics of computing.