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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
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Management Information SystemsByEffy 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) • 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
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
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