Management Information Systems By Effy Oz Andy Jones
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 MP 3 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, Java. Script, J 2 EE, 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 My. SQL 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
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