IT Fundamentals: What is a Computer?

IT Fundamentals

• IT Fundamentals is listed as course 04:547:201

Overview

• Introduces key concepts: "What is a computer?", "What is programming?", and the history of both.
• Emphasizes the importance of understanding IT as both a tool and a discipline.

What Is a Computer

• Explores the distinction between hardware and software components.
• Defines the relationship between data, information, and knowledge.

Computer Defined

• A computer is an electronic device that processes data input to generate output.
• Computers are programmable machines performing high-speed mathematical or logical operations.
• Computers function exactly as instructed.
• The essential components include CPU, Input/Output devices, and Memory.
• CPUs handle arithmetic and logic, while Input/Output allows the computer to interact with the outside world.
• Memory is primarily accessible to the CPU and can be extended with secondary storage.
• Electronic signals are the input, with "High" representing 1 and "Low" representing 0.
• Computers only understand machine language.

Computer Types by Generation

• Supercomputers are for complex scientific and research tasks, and use parallel processing and typically cost tens to hundreds of millions of US dollars.
• Mainframe computers focus on organization-level processing and usually cost hundreds thousands of US dollars.
• Minicomputers serve smaller organizations are generally priced at thousands of US dollars
• Servers are for large scale storage and manage file requests and cost tens of thousands of US dollars.
• Workstations (personal computers) for high performance tasks, costing up to twenty thousand of US dollars.
• Personal computers/laptops are for simple small processing tasks, and cost about 500 to 1200 US dollars
• Mobile devices, are handheld and cost about 100 to 700 US dollars.

Classifying Computers

• Computers are classified as special-purpose vs. general-purpose.
• Some computers are intended for many users.
• Computer sizes vary from minicomputers to desktops.
• Computer price range is from hundreds to millions.
• Computers do what they are told to do.

IPOS Cycle

• Computers operate through the Input-Processing-Output-Storage (IPOS) cycle.

I: Input

• Involves acquiring data and instructions from external sources via hardware like keyboards or networks. Through input devices (keyboard, disk file, network, mic)

P: Processing

• Executes program instructions using the processor with data and instructions stored in memory.
• This includes data movement between the CPU and memory, I/O operations, arithmetic/logic tasks, and branching to different program locations.
• Includes data movement between CPU and memory.
• Includes Input/Output to move data between CPU or memory.
• Includes arithmetic/logic operations for computation
• Branches change to another location in the program

O: Output

• Sends results from program code to output devices like a monitor or printer.
• Output devices also include speakers.

S: Storage

• Retains data for persistence.
• Storage medium include hard disks, solid-state drives, optical discs or magnetic tape.
• Solid state Drives (SSD) and Hard Disk Drives (HDD) are types of storage

Computing System Components

• Hardware consists of physical elements (printers, circuit boards, wires, keyboards).
• Software includes the instructions, or programs, for computers to execute.
• Abstraction is a mental model that simplifies complex details.

Software Defined

• Software is critical for controlling hardware and includes the operating system (OS).
• OS handles fundamental operations, disk, processor access and device communication.
• Programs running on the OS consist of instructions, applications, and languages.

CPU Execution

• The CPU executes programs using a specific instruction set.
• Instruction sets and their rules define machine language, which is directly executable by computers.
• Machine code is binary or hexadecimal.
• Language translators such as Assemblers turn primitive assembly language programs into machine language.
• Compilers convert high-level language programs into machine language.

Code Comparison

• Demonstrates how high-level code translates into assembly code and machine code.
• Highlights that 1 'C' instruction is equivalent to multiple assembly and machine instructions.

Processors and Registers

• Processors use registers to store immediate data.
• Dedicated CPU registers store program instructions, the current instruction, and data.
• Registers store the address of next program instruction in memory, the current instruction to be executed, and execute data the current uses.

Memory

• Registers are for short term usage
• Short term memory stores the program code and data

System and Application Areas

• System areas involve the study Algorithms and Data Structures, Programming Languages, Operating systems etc
• Application Areas encompass Numerical and Symbolic Computation, Intelligent Systems, Computational Science etc

Information Technology (IT) Defined

• IT involves data gathering and processing, information dissemination, and infrastructure maintenance.
• Combines people, computing resources, software, data, and networks.
• IT personnel designs, builds and maintains computing systems, while providing administrators that have roles, such as systems and support.
• IT Administrators are in charge of IT infrastructure.
• IT makes information accessible.

IT Roles

• System, network, and database administration.
• Web administration and development.
• Security administration.
• IT Admins handle installation, security, networking and manages databases
• IT Support offers support to end uses

IT Administrator Tasks

• System administrators manage computers, install software, and troubleshoot systems.
• Network administrators configure networks and ensure security.
• Database administrators manage databases.
• Web administrators maintain websites.
• Web developers design web pages.
• Security administrators secure computer systems by configuring firewalls and security policies.

IT Support

• IT personnel support end-users with documentation, training, help desk support.

Large Scale IT Users

• Business uses IT for e-commerce and customer records.
• Education utilizes IT for scholastic record-keeping and teaching support.
• Entertainment relies on IT for digital editing and music creation.
• Government applies IT for record-keeping, intelligence, and dissemination of information.
• Healthcare uses IT for storing medical records.
• Manufacturing leans on IT for design and automation.
• Research handles computations and dissemination of information.

IT Studies

• Individuals engage with IT as hobbyists, gamers, scientists, and business professionals.
• Formal IT education is available through 4-year and 2-year degree programs
• Individuals can get IT traning from Technical schools or by learning on their own.

IT Skills

• Troubleshooting and problem-solving identifies and rectifies technical issues.
• Knowledge of operating systems, application software, and system monitoring is essential.
• System-level programs uses scripting to automate processes.
• System security is in place for threat detections with a security policy for its users
• Hardware skills include installing, configuring, and repairing IT hardware.

Preparedness in IT

• Continuous learning about new trends in technology is essential.
• Ethical behavior is expected, requiring knowledge of ethical and unethical boundaries.

History of Computing

• Early computing evolved from counting to digital devices.
• Counting with stones.
• Geared machines performed primitive calculations.
• Mechanical calculators with calculations & storage
• Digital computing

Early Computing Devices

• Abacus being the earliest counting device known
• Pascaline calculator developed for addition and subtraction.
• It was developed by Pascal
• Leibniz enhanced it with multiplication and division
• Joseph Marie Jacquard invented a programmable loom.

Father & Mother of Computers

• Charles Babbage invented Difference Engine (1822), but never finished, whereas
• Ada Lovelace, the first computer programmer.
• Charles Babbage is the father of the computer.
• Ada Lovelace used loops/conditionals

Mechanical Punch-Card Computers

• Herman Hollerith created electrically-driven mechanical tabulator around 1890.
• His machine could calculate using punch cards that closed electrical circuits.
• This sped up the US census from 7.5 years to 6 weeks and, in 1911, Hollerith's Company became IBM.
• Herman Hollerith invented punchcards and used punchcards & metal rods

Computer Evolution (1st Generation)

• Gears were replaced with electronic switches.
• Early computers were electromechanical, non-programmable, or specialized.
• 1946-1959: ENIAC first computer.
• Created at University of Pennsylvania, it cost $500,000 in 1940s and had 17, 468 vacuum tubes
• In the late 1800s and into the 1900s, gears were replaced by electronic switches Early computers (in the 1930s and 1940s)
  • Electromechanical – electricity to rotate gears
  • Non-programmable
  • Programmable but only special-purpose
• Electronic Numerical Integrator and Computer (ENIAC) was the first 1st electronic, general-purpose computer
• Developed at Upenn

Three Problems of the First Generation of Computers

• All memory instructions and I/O had to be part of program because there was no OS
• Programmed in difficult machine language
• Vacuum tubes has a short shelf life
• Expensive

Digital Computing's Origins

• Alan Turing helped to break down difficult problems
• Grace Hopper codified human readable languages

Computer Evolution (2nd Generation)

• Transistors replace vacuum tubes in 1959-1963.
• Transistors were smaller, cheaper and more reliable
• Magnetic core memory began
• Computer companies, sold mainframe computers
• OS and high level languages arrive
• Cheaper and faster computers at a smaller size
• Resulted in faster computer development
• Magnetic core memory was introduced for main memory
• Development of Mainframe Computers
• First OS developed & external disk devices

Vacuum Tubes and Transistors

• Vacuum tubes were first used in electronic computers in 1941,
• Transistors replaced vacuum tubes in 1948.

Integrated Circuits

• Integrated circuits are made from semiconductors

The History of Computer Generations

• First Generation (1946-1959): Vacuum Tubes.
• Second Generation (1959-1963): Transistors.
• Fourth Generation (1974) Microchips.

Computer Evolution (3rd Generation)

• 1964-1974, IC chips inserted into the motherboard
• The integrated circuits replaced traditional trransistors
• Minicomputers could service 10 to 100
• OS that ran efficiently
• Printed integrated circuits into silicon chips
• These chips were inserted into motherboards
• Mainframe & minicomputers
• Computer families that ran the same software resulting in better programming langauges

Computer Evolution (4th Generation)

• In fourth generation computers are developed
• A single integrated chip can hold one CPU in 1974
• A single chip can do as much work as a room full of circuits
• Gordon Moore determined that the doubling of transistors doubles approximately every 18-24 months
• Moore's Law doubling continued until 2012
• Started with the development of the microprocessor
  • A CPU on a single chip
  • Small CPU = small computer
• Transistors started to double every year
• SSI – small scale integration (10- 20 transistors/chip)
• MSI – midscale integration (100-200 transistors/chip)
• LSI – largescale integration (1000s transistors/chip)
• VLSI – very largescale integration (100,000s transistors/chip)
• ULSI – ultra largescale
• Moore’s law - transistors doubled every 18-24 months
• Grace Hopper was the first person to de-bug a computer program.
  • She Programmed UNIVAC (Universal Automatic Computer) & COBAL (programming language)
• Alan Turing helped break the Enigma Code and is considered the father of modern computer science

Problem Solving

• Problem solving is to understand the problem
• Devise a plan
• Carry out the plan
• Look back
• Understand
• Development of a plan
• Write the steps
• Testing

Strategies Used for Breaking Down Large Computing Tasks

• Never reinvent the wheel, and instead plug in programs with similar solutions
• Divide and Conquer: Divide and conquer a task

Computer Problem-Solving Phases

• Analysis and Specification, Algorithm Development, Implementation, Maintenance.
• Analyze
• Specification Algorithm
• Development Phase
• Develop algorithm
• Test algorithm
• Implementation Phase
• Code algorithm
• Test algorithm
• Maintenance Phase
• Use
• Maintain

Algorithms

• Algorithms are a finite set of instructions that solves a problem in a finite period of time
• Abstract Step: Algorithmic step containing specific details
• Concrete Step: An algorithm step in which details are specified
• A formula for problem-solving

How to Develop Algorithimcs

• There should be a well developed Top-down Design that focuses on the work at hand
• An object oriented design that is well focused on the data involved
  • Top-down design focuses on the tasks to be done
  • Object-oriented design focuses on the data involved in the solution.

Selection Determined Algorithm

• Algorithms uses "if" statements and loops

Methodology Summary

• Methodology is to analyze the problem, list main tasks, write the remaining modules and sequence and revise accordingly
• Analyze the problem, list tasks, write modules, and re-sequence and revise as needed.