Introduction to Computing Notes

Corporate Computing Revolution

Corporate computing has revolutionized the business environment by aiding in complex tasks like bookkeeping, accounting, inventory control, customer databases, shipping control, and financial analyses. Desktop computers are now versatile and inexpensive, replacing typewriters and personal assistants for word processing and organizational services. Networking company computers allows access to resources and information, reducing paperwork and increasing information flow.

A Brief History of Computers

To understand the importance of IT, it is crucial to appreciate its origins and developments, particularly in the United States.

The First Computer

Charles Babbage, a 19th-century British mathematician, conceptualized the first computer, the 'analytical engine,' which included a programmable logic center with memory. However, it was never built.

Colossus became the first electronic, digital, programmable computer, used by British codebreakers to decipher German messages during World War II.

Subsequent Developments

In 1946, ENIAC (Electronic Numerical Integrator and Calculator) was used at the University of Pennsylvania. It was designed for artillery firing calculations and was the first general-purpose digital electronic computer in America. ENIAC used vacuum tubes, making it faster than the Mark I, which used electromechanical relays. The Mark I, Colossus, and ENIAC utilized the binary system (0 and 1), which is compatible with computer operation through on-off switches called logic gates that produce information called 'bits'.

In 1947, Bell Labs invented the transistor, which replaced the vacuum tube, and later created Leprechaun, the world's first fully transistorized computer. William Shockley, a transistor inventor, founded his own firm in Palo Alto, California, which became Silicon Valley.

Interconnected transistors could be placed on a silicon microchip. Although initially 'hard-wired', Intel Corporation's invention of the microprocessor allowed single chips to perform various tasks. These advances reduced the size and cost of computers, leading to personal computers.

The first personal computer was the Altair 8800 in 1975 and two years later, the Apple II was unveiled. In 1981, IBM introduced its PC with the Intel microprocessor, setting a quality standard.

Introduction to Computing

Computers have positively impacted medicine, providing precise measurements and monitoring for surgical anesthesia, blood testing, and intravenous injections. In 1982, Time named the computer the 'Machine of the Year'.

The Information Technology Boom

By the mid-1980s, the computer craze was at its peak. Many computer-related companies went public, raising substantial capital. By 1984, retail sales of personal computers and software reached $15$ billion. The computer aftermarket, including training, custom furniture, and publishing, generated $1.4$ billion in sales.

Microsoft was the largest software manufacturer, with 1984 revenues of approximately $100$ million. Systems software, like Microsoft's MS-DOS and AT&T's UNIX, instructed computer systems to work together. Lotus 1-2-3, a spreadsheet plus electronic filing system, was also popular. Software quality and prices varied.

The Advent of Computer Viruses

By 1988, computer viruses became a major concern, infecting over 250,000 computers in nine months and raising concerns about data vulnerability. The first computer virus criminal trial took place in Fort Worth, Texas, involving a disgruntled ex-employee accused of infecting his former company's system, deleting 168,000 sales commission records. These viruses replicated themselves, infecting software and data unpredictably.

The computer revolution of the 1980s presented both opportunities and perils.

Supercomputers

Supercomputers, costing between $5$ million and $25$ million each, were used to locate oil deposits, create special effects, and design military weapons, along with artificial limbs and jet engines. These machines processed data measured in gigaFLOPS (billions of operations per second). The US National Science Foundation established five supercomputer centers linked to 200 universities and research labs. In 1988, IBM financed a parallel-processing machine with 64 processors, making it 100 times faster than current supercomputers, and was developing the TF-1 with 33,000 high-speed processing units. The world's fastest supercomputer (in June 2015) was the Tianhe or TH-2, a 33.86 Petaflop supercomputer.

Smartphones

Alexander Graham Bell invented the telephone in 1878.

Motorola introduced the first cellphones in the 1980s. These phones were bulky, expensive, and had short battery life.

The first smartphone was developed by IBM and BellSouth in 1993, featuring a touch screen capable of accessing email and sending faxes.

Smartphones have GPS, video recording, and various applications. Text messaging is a prevalent form of communication. Smartphones interpret QR codes, and current models have 4G LTE internet, motion sensors, and mobile payment capabilities. Some smartphones can respond to voice commands, answer questions, and control home devices.

What is a Personal Computer?

Personal Computers (PCs) are small, inexpensive computers for individual users, typically running Microsoft Windows operating system.

PCs contain hardware components, both internal and external (peripherals).

The language of computers is the bit, with data stored as sequences of 0s and 1s. Storage is measured in kilobytes (KB), megabytes (MB), gigabytes (GB), or terabytes (TB). Note that $1$ KB is $1024$ bytes, not $1000$ in the metric system.

Storage Capacity Indicators Table:

$1/0 = bit$
$8 bits = 1 Byte$
$1024 Bytes = 1 KB$
$1024 KB = 1 MB$
$1024 MB = 1 GB$
$1024 GB = 1 TB$
$1 petabyte = 1 quadrillion bytes$

A terabyte can store approximately 20 million typed pages. The U.S. Library of Congress contains approximately 3 petabytes of data.

PC Hardware and Software

Computer Hardware

Tangible, physical parts of a computer system, including the case, monitor, keyboard, mouse, hard disk drive, motherboard, and video card.

Computer Software

Instructions in programming code that control the computer hardware. It is installed from a CD or other medium.

PC Hardware Components

1. System Unit: Contains internal components like the motherboard, CPU, ROM, RAM, disk drives (HDD/CD/DVD), and system board.
2. Keyboard: Used for data entry and modification.
3. Mouse: A pointing device for task selection.
4. Monitor: Provides visual output.
5. Printer: Produces hard copies.
6. Audio speakers: For sound.
7. Communication devices: Wireless and Bluetooth devices.
8. Minor peripherals: Web-cams, flash drives, headphones, etc.

Internal Hardware Components:

Motherboard: The main circuit board with chips, circuitry, and slots for other components.

CPU: The "brain" of the computer where calculations take place. The CPU retrieves program instructions, decodes and executes them, performs arithmetic operations, and sends results back.

Multi-Core Processors: A single computing component with multiple processing units called 'cores'.

Smartphones also have CPUs with power saving, graphics, and computing performance features.

Memory:

• RAM (Random Access Memory): Temporary storage that holds data when a program is open or a spreadsheet is in use. It is volatile, meaning data is lost when power is cut.
• ROM: Permanently stores programs used in the booting process.

Drives: Used for storing information:

1. Hard Disk Drive (HDD): Secondary or permanent storage that saves programs and personal documents using magnetic marks on metal plates, has two connection standards: IDE and SATA.
2. Solid State Drive (SSD): Stores data on interconnected flash memory chips, faster and more durable than an HDD.
3. CD-DVD Combo Drives: Read and write to optical disks (CD-ROM, CD-R, CD+R, CD-RW, DVD-R, DVD+R) for data storage and multimedia.

PSU (Power Supply Unit): Converts 240V to internal component-friendly voltages (3V, 5V, 12V).

UPS (Uninterruptible Power Supply): A backup battery for power outages.

Ports: Located at the back of the PC for connecting external devices:

• PS2 Ports: For mouse (green) and keyboard (purple).
• Serial Ports: For external devices like PC screens and modems.
• USB (Universal Serial Bus): For printers, digital cameras, flash drives, cell phones, etc.
• HDMI (High-Definition Multimedia Interface): Transmits video and audio signals.
• LAN Port: For network cable.
• Audio Ports: Headphone jack and mic.

PC Software

Software acts as the interface between the user and the hardware. It is written in a programming language but translated into machine language for the CPU.

Software is divided into System Software and Application Software.

System Software: Interacts with the computer at a basic level. The Operating System (OS) is system software. Examples include Windows XP/Vista/7/8/10, Linux, etc.

Operating systems use a Graphical User Interface (GUI) with icons for user interaction.

Application Software: Programs for common information processing jobs, like word processing, spreadsheets, database management, and graphics. It must be compatible with the system software.

Hardware/Software Interaction

A computer works with data. Data is processed by software and hardware components to produce a useful result.

The IPOS Cycle (Input, Processing, Output, Storage)

Input: Data entered into the computer using input devices like a keyboard, mouse, or scanner.

Processing: The processor chip interprets and executes instructions, with temporary storage in computer memory.

Output: An output is generated, which can be saved or displayed on a monitor. Output devices convert machine language into human-readable language.

Storage: Data is stored on a storage device for later retrieval, such as hard disk drives, flash drives, and CDs/DVDs.

Upgrading your PC

PC slowdown is caused by start-up programs, junk files, and dust.

Software Upgrade

Changing software settings can improve performance. Consulting a professional is advisable.

Software tune-ups include:

1. Disabling unwanted start-up programs.
2. Cleaning up unnecessary system files.
3. Defragmenting hard drives.
4. Keeping the PC free from viruses and malware.
5. Upgrading the operating system.

Hardware Upgrade

Cleaning the inside of a PC helps prevent slowdown due to heat. For PCs a few years old, consider upgrading:

1. Replacing HDD with an SSD
2. Upgrading RAM capacity
3. Upgrading the CPU or graphics card for gaming

Network Concepts

A computer network is two or more computing devices connected for sharing resources, such as Internet connections, printers, file servers, and information.

Benefits of sharing resources include:

1. Saving disk space and securing sensitive information.
2. Enabling multi-user application software.
3. Sharing hardware to reduce costs.

Basic Network Components

• Clients: Computers that access and use the network.
• Servers: Hold shared files, programs, and the network operating system.
• Network Operating System (NOS): Enables network nodes to communicate.
• Network Interface Card (NIC): Allows a computer to communicate over a network, with wired(cables) and wireless options(radio waves/antenna).
• Hub: Connects computers together.

The most common network is a Local Area Network (LAN), spanning a small area. The Internet is composed of many LANs, forming the World Wide Web (WWW), a Wide Area Network (WAN).

Cloud Computing

In cloud computing, data and programs are accessed over the Internet rather than from a local hard drive.

Examples include:

• Search queries on Google
• Web-based email (Hotmail, Gmail)
• Web-based document preparation (Google Documents)

Role of Computers in the Workplace

Computers are vital in many workplaces, aiding in data analysis and daily communications. They are nearly essential for organizational survival in a competitive market.

Automation and Improved Efficiency

Computers automate repetitive tasks with fewer mistakes, and advancements have led to business- and consumer-focused apps for organization and productivity.

Improving Communication

Computers led to the Internet and mobile devices, enabling global communication and changing work flow.

Printing and Publication Technology

Computers replaced typewriters, revolutionizing office business and increasing productivity.

Database Technology

Computers store data, allowing employees to run payroll, calculate taxes, and create financial reports efficiently.

Workplace Culture

Computers enable telecommuting, which can impact workplace morale and teamwork.

The Windows Operating System

Introduction to Operating Software

An operating system (OS) manages hardware operations and provides support services for users and applications.

Modern operating systems use a Graphical User Interface (GUI) with icons, buttons, and menus.

Common operating systems include:

Microsoft Windows

Owned by Microsoft and installable on various computers.

Ubuntu

A free, open-source OS based on Linux, updated every six months.

Mac OS X

Pre-installed on Apple Macintosh computers. and is not open source.

iOS

Apple's mobile OS for iPod, iPhone, and iPad devices that is not open source but has most applications available.

Android

A customizable OS maintained by the Open Handset Alliance, allowing manufacturers to add unique features.

Getting Started with Windows

Logging On to Your PC

Windows requires a username and password for account security.

How to Set Up a New User Account

1. Click the Start Button on the Task bar.
2. Open the Control Panel and click on User Accounts
3. Click on the Manage Accounts link

Accounts can have standard user or administrator rights.

The Desktop

The desktop displays menus, windows, icons, and files.

Aero Peek previews windows from grouped taskbar applications.

The Taskbar

The Taskbar shows open programs and files and includes:

• Start button
• Notification area
• Pin feature

Clicking the Start button displays the Start Menu:

• Account Name
• Computer
• Documents
• Pictures
• Music
• All Programs Menu
• Search programs and files
• Recently Used Programs
• Help and Support
• Devices and Printers
• Control Panel
• Shut Down
• Run Command
• Display Desktop

Display Desktop hides all open windows.

Objects

Basic Windows components include:

1. Files: Documents saved in a folder or on the Desktop.

2. Shortcuts: Provide easier access to programmes/files and this are represented by a path to the original file.

   *NOTE: Don't copy a Shortcut of a document thinking that you are sending your colleague the original document. You are actually copying the path to the document and not the document itself, meaning it will not be viewable to the person who you sent it to.

3. Containers: A disk, folder or Recycle Bin.

The Recycle Bin

Temporarily stores deleted data, which can be restored. Emptying the Recycle Bin removes the files permanently. Files deleted from a floppy disk, flash drive or network are permanently remove