Management Information Systems By Effy Oz & Andy Jones Chapter 4: Business Hardware and Software www.cengage.co.uk/oz

Objectives List major hardware components of computers and explain their functions Classify computers into major categories, and identify their strengths and weaknesses Identify and evaluate key criteria for deciding what computers or related devices to purchase

Objectives (continued) Discuss the possible health hazards of computer use Explain the difference between application software and system software Enumerate the different generations of programming languages and explain how they differ

Objectives (continued) Cite the latest major developments in application and system software Clarify the differences between proprietary software and open source software List characteristics that are important in evaluating packaged software applications for business use Understand the problem of software piracy and how it affects businesses and consumers

Hardware Components Hardware: physical computer components Consider software before hardware Computer must handle four operations Accept data Store data Process data Output data

Hardware Components (continued)

Hardware Components (continued) Input devices: receive signals from outside of computer and transfer them into computer Central processing unit Accepts instructions and data Decodes and executes instructions Stores output in memory

Hardware Components (continued) Internal memory: stores data and instructions before and after CPU processes them RAM: random access memory ROM: read-only memory Motherboard: CPU and primary memory reside

Hardware Components (continued) External Memory: magnetic disks, magnetic tapes, optical discs, DVDs, and flash memory Allows permanent storage Output devices: deliver information from computer to person Most commonly monitors and printers Includes audio devices

Hardware Components (continued) Bit: Binary digit 0 or 1 Byte: a standard group of eight bits Most characters represented by single byte

Hardware Components (continued)

Classification of Computers Computers vary in size Classified by power Depends on processing speed and memory size More powerful computers are more expensive

Supercomputers Supercomputers: most powerful computer at any given time Largest in physical size and most expensive Parallel processing: multiple processors running simultaneously Also known as multiprocessing

Mainframe Computers Mainframe computers: store large amounts of data and business transactions Less expensive and less powerful than supercomputers Banks, universities, and insurance companies use them as a central computer 40-50% of world’s business data resides on mainframes Use multiple processors

Midrange computers Midrange computers: often act as servers within organisations or through the Internet Smaller and less powerful than mainframes Serves hundred of users that connect from personal computers Use multiple processors

Microcomputers Microcomputers: personal computers, notebook computers, and handhelds Workstation: more powerful microcomputer used for CAD, CAM, and scientific applications Power doubles about every two years

Computers on the Go: Notebook, Handheld, and Tablet Computers Notebook computer: compact personal computer powered by rechargeable battery New models include wireless technology Personal digital assistant: handheld computer Stylus used to enter data through touch screen Tablet computer: PC on a thick writing tablet

Converging Technologies Technology convergence: build several technologies into single piece of hardware Prominent in handheld units Commonly merged technologies include Cell phones Television Digital cameras MP3 players

A Peek Inside the Computer Professionals must know computer components to understand its power and capabilities Use the knowledge to make good decisions in purchasing a computer

The Central Processing Unit CPU has two units to store and process data Control unit and arithmetic logic unit CPU is silicon chip with multiple circuits Also known as microprocessor Modern processors can do multithreading Processing more than one program at a time

The Central Processing Unit (continued) Microprocessors are embedded with transistors Transistor is a semiconductor that can represent binary code’s two states Machine Cycle (CPU): Fetch, decode execute each instruction Data word: maximum number of bits that the control unit can fetch Arithmetic Logic Unit: arithmetic and logic

Computer Power Computer power depends on processing speed and memory capacity Bus: electronic lines or traces used for communication inside computer Throughput: number of bits per second bus can accommodate MIPS: millions of instructions per second, a common measure of computer speed

Input Devices Computers must receive input to produce output Input devices include machines used to enter instructions and data into computer Most common input device is keyboard

Keyboard Contains keys that users press to enter data Includes letters, numbers, and punctuation QWERTY and Dvorak: QWERTY standard Dvorak facilitates faster typing Ergonomic keyboard: fits the natural position of forearms and prevents injury

Mouse, Trackball, and Trackpad Mouse: controls onscreen pointer to facilitate point-and-click approach Trackball: similar to mouse, but ball moves within device Trackpad: cursor controlled by touch-sensitive pad Mice and similar devices can be wireless units

Touch Screen Touch screen: both input and output device Often used for public applications Prevalent in handheld devices

Source Data Input Devices Source data input devices: copy data directly from source Bar-codes, credit cards, and checks Use optical recognition devices, which detect positions of marks or characters Magnetic-ink character recognition: detects magnetic ink on cheques

Imaging Imaging: converting documents into images Saves paper More efficient retrieval and filing Scanned document can be destroyed after scan

Speech Recognition Translating human speech into computer-readable data and instructions Receive input from microphone and process with software May increase noise level in offices

Output Devices Most popular devices are monitors and printers Other output includes speakers

Monitors Cathode-ray tube: inner side of screen has layer of phosphoric dots called pixels Electron gun receives instructions from computer and sweeps the pixels Flat-panel monitor: includes liquid crystal display, which uses a liquid crystal filled screen, whose molecules align in different places when given electric charge

Printers Nonimpact printer: does not mechanically impact the paper Laser printer is most common in business Others: ink-jet and electrothermal printers Impact printers: reproduce image by using mechanical impact Dot-matrix printer has pins that strike ink ribbon against paper

Storage Media Data must be stored on nonvolatile medium Data is retained even when not powered Storage devices differ in technology used to maintain data and physical structure

Modes of Access Sequential storage: data is organized one record after another Slower and less convenient Direct access: records are organized by physical address on the device Flash drives: small storage devices that connect via universal serial bus Direct access storage media is only practical way to organize and query databases

Modes of Access (continued)

Magnetic Tapes Magnetic tapes: similar to tape recorders and VCRs Provide lowest cost (bytes per dollar) Can backup all data Takes long time to copy from tape Unreliable after a long period of time

Magnetic Disks Magnetic disk: most widely used storage medium Hard disk: stack of several aluminum platters installed in same box that holds CPU Stores up to 500 GB of data External hard disks connect to computer through USB port

Optical Discs Optical disc: recorded by treating disc surface to reflect light in different ways Compact discs: available as read-only, recordable, and rewritable DVDs: store 4.7 GB per side Optical discs are slower than hard disks

Optical Tape Optical tape uses same technology as optical discs to store and retrieve data Bits are organized sequentially like tape Used in digital video camcorders

Flash Memory Flash memory: memory chip that can be rewritten and holds content without power Available as memory card and USB drive Solid state disk: storage media that does not have latency time

Business Considerations in Evaluating Storage Media When purchasing storage devices managers must consider: How the data is used Capacity of the device Speed and cost Reliability and portability

Business Considerations in Evaluating Storage Media (continued)

Considerations in Purchasing Hardware Companies must consider the following when deciding what to purchase: Power of the equipment Expansion slots and ports Monitor type and resolution Ergonomics

Considerations in Purchasing Hardware (continued) Other factors include: Compatibility with existing hardware Physical size of computer Reliability of vendor Power consumption and noise Scalability

Software: Instructions to the Computer Applications: programs that contribute to productivity Software: series of instructions to execute processes Software categories: Application software: enables task completion System software: enables applications to run on computer

Programming Languages and Software Development Tools Programs needed for every computer operation Programming: process of writing programs Machine language: language hardware understands 0’s and 1’s Assembly language: easier to program than machine language Uses words High-level programming language: English-like statements

Programming Languages and Software Development Tools (continued) Software development tools: develop software with little knowledge of programming languages Third-generation languages known as “procedural” languages Programmer must detail logical procedure Fourth-generation languages closer to human language Debugging: locating and fixing program errors

Programming Languages and Software Development Tools (continued)

Programming Languages and Software Development Tools (continued)

Visual Programming Visual programming languages: create graphics by selecting icons from palette Microsoft Visual Basic Borland Delphi Visual C++ User can still work at the code level

Object-Oriented Programming Object-oriented programming: modular approach to programming Ease of maintenance Object contains data elements and methods that perform functions Objects reusable and combined in complex programs Include C++, Object Pascal, and Java

Object-Oriented Programming (continued) Increasing amount of software developed for Web Web programming languages include Java, JavaScript, J2EE, and PHP Applet: code produced by Web programming language Runs same on different operating systems

Object-Oriented Programming (continued)

Application Software Application can be software to let nonprogrammers develop their own tools Application-specific software: performs specific jobs General-purpose application software: serves multiple purposes Usually comes as packaged software Packaged software: ready to install from external storage medium

Office Productivity Applications Productivity tools: assist normal office work Word processors: type letters and articles Spreadsheets: store numbers Perform complex mathematical, statistical, and financial functions Presentation tools: develop impressive presentations quickly

Office Productivity Applications (continued) File management tools: create and manipulate local or shared databases Graphics programs: create intricate graphics Manipulate digital photographs Desktop publishing tools: Pamphlets Cards Calendars

Office Productivity Applications (continued) Project management tools: plan projects and track progress Suite: collection of various applications Perform multiple interrelated functions

System Software System software: deals with essential operations User interface Loading files Copying files Managing memory resources Encompasses compilers and interpreters Applications must be compatible with system software

Operating Systems Operating system: most important program Recognizes input from keyboard Sends output to computer display Keeps track of files and directories Runs applications

Operating Systems (continued) Operating system manages memory Also known as “platform” Interacts with user and CPU Utilities: another OS functions Hardware diagnostics Disk check File sorting

Operating Systems (continued) Operating system functions include user interface Originally text prompts Later graphical user interfaces Operating system must allocate memory Virtual memory: hard disk acts as RAM

Operating Systems (continued) Plug-and-play: run a device as soon as you physically attach it Driver: enables OS to control device Operating systems incorporating more services Database management Networking Security

Operating Systems (continued) Current operating systems Windows XP Linux Mac OS Linux: Free OS Based on UNIX Some versions of Windows notoriously unstable OS based on UNIX highly stable

Operating Systems (continued)

Operating Systems (continued)

Other System Software Other system software Compilers Interpreters Communications software Utilities Communications software supports transmission and reception of data across networks Utilities include antivirus programs, firewalls, and spyware eliminators

Open Source Software Proprietary software: sold for profit Private code Developer retains rights to software Open source software: free source code Fewer bugs because many programmers review Mozilla Firefox Thunderbird MySQL PERL

Open Source Software (continued) Not all free software is open source Microsoft Internet Explorer Linux best known open source operating system Popular because of versatility Runs on: Mainframes Handhelds Electronic devices

Software Licensing Software is usually licensed Licensed software: limited permission Time-limited license requires annual fees Several models Permissive model Anyone can use and sell modified versions General public license Cannot sell for profit

Considerations for Packaged Software Many goals and custom requirements during development process Factors when purchasing large software packages more complex Cost Time to implement Cost of interrupting operations Modification costs

Summary Understanding hardware is important for purchasing decisions Computers classified according to power All computers have CPU to process instructions Clock rate measures the speed of a CPU Computer word is the number of bits it can process in a single cycle

Summary (continued) Computer power: speed and memory size RAM is volatile memory that forms a large part of computer’s memory ROM is nonvolatile: does not require power Imaging devices help process text and graphics When evaluating external storage, consider density, transfer rate, capacity, portability, format

Summary (continued) Data organized sequentially on tapes Direct access storage devices include RAM, magnetic disks, and optical discs Databases require direct access storage devices When purchasing hardware, managers should consider power, scalability, and compatibility

Summary (continued) Information technology may pose health risks such as carpel tunnel syndrome Software is collective term for computer programs Software classified as: system or application Programming languages and software development tools help develop software

Summary (continued) Increasing amount of software is linked to Internet Some application programs custom designed, and many are packaged Office productivity tools such as word processors and spreadsheets help worker efficiency

Summary (continued) Most important system software is operating system Open source software Distributed freely More reliable