fundamentals of information systems, sixth edition

Fundamentals of Information Systems, Sixth Edition

Chapter 2 Hardware and Software

Principles and Learning Objectives

• Computer hardware must be carefully selected to meet the evolving needs of the organization and its supporting information systems– Identify and discuss the role of the essential

hardware components of a computer system– Identify the characteristics of and discuss the usage

of various classes of single-user and multiuser computer systems

Fundamentals of Information Systems, Sixth Edition 2

Principles and Learning Objectives (continued)

• The computer hardware industry and users are implementing green computing designs and products– Define the term green computing and identify the

primary goals of this program



• Systems and application software are critical in helping individuals and organizations achieve their goals– Identify and briefly describe the functions of the two

basic kinds of software– Outline the role of the operating system and identify

the features of several popular operating systems



• Organizations should not develop proprietary application software unless doing so will meet a compelling business need that can provide a competitive advantage– Discuss how application software can support

personal, workgroup, and enterprise business objectives

– Identify three basic approaches to developing application software and discuss the pros and cons of each



• Organizations should choose a programming language whose functional characteristics are appropriate for the task at hand, considering the skills and experience of the programming staff– Outline the overall evolution and importance of

programming languages and clearly differentiate among the generations of programming languages



• The software industry continues to undergo constant change; users need to be aware of recent trends and issues to be effective in their business and personal life– Identify several key software issues and trends that

have an impact on organizations and individuals


Why Learn About Hardware and Software?

• Organizations invest in computer hardware to:– Improve worker productivity– Increase revenue, reduce costs– Provide better customer service

• Managers:– Are expected to know enough about their business

needs to be able to ask tough questions


Computer Systems: Integrating the Power of Technology

• To assemble an effective and efficient system:– You should select and organize components while

understanding the trade-offs between overall system performance and cost, control, and complexity

• Hardware objectives are:– Subordinate to, but supportive of, the information

system and the current and future needs of the organization


Hardware Components

• Central processing unit (CPU): – Arithmetic/logic unit, the control unit, and the register

areas• Arithmetic/logic unit (ALU):

– Performs mathematical calculations and makes logical comparisons

• Control unit:– Sequentially accesses program instructions,

decodes them, and coordinates the flow of data in and out of the ALU, registers, primary storage, and even secondary storage and various output devices


Hardware Components (continued)


Processing and Memory Devices: Power, Speed, and Capacity

• System unit:– Houses the components responsible for processing

(the CPU and memory) • All other computer system devices:

– Are linked either directly or indirectly into the system unit housing


Processing Characteristics and Functions

• Clock speed:– Series of electronic pulses produced at a

predetermined rate that affects machine cycle time– Often measured in:

• Megahertz (MHz): millions of cycles per second• Gigahertz (GHz): billions of cycles per second

• Physical characteristics of the CPU– Most CPUs are collections of digital circuits

imprinted on silicon wafers, or chips, each no bigger than the tip of a pencil eraser


Memory Characteristics and Functions

• Memory:– Provides the CPU with a working storage area for

programs and data– Rapidly provides data and instructions to the CPU

• Storage capacity:– Eight bits together form a byte (B)



Memory Characteristics and Functions (continued)

Memory Characteristics and Functions (continued)

• Types of memory:– Random access memory (RAM):

• Temporary and volatile– Read-only memory (ROM):

• Nonvolatile• Provides permanent storage for data and instructions

that do not change


Multiprocessing

• Multiprocessing:– Simultaneous execution of two or more instructions

at the same time• Multicore microprocessor:

– Combines two or more independent processors into a single computer



Multiprocessing (continued)

• Parallel computing:– Simultaneous execution of the same task on multiple

processors to obtain results faster• Grid computing:

– Use of a collection of computers to work in a coordinated manner to solve a common problem


Secondary Storage and Input and Output Devices

• Secondary storage:– Compared with memory, offers the advantages of

nonvolatility, greater capacity, and greater economy– Considerably slower than memory

Access Methods

• Sequential access:– Data must be retrieved in the order in which it is

stored– Devices used called sequential access storage

devices (SASDs)• Direct access:

– Records can be retrieved in any order– Devices used are called direct access storage

devices (DASDs)


Secondary Storage Devices

• Magnetic tapes:– Primarily for storing backups of critical organizational

data• Magnetic disks:

– Direct-access storage device• Redundant array of independent/inexpensive disks

(RAID):– Method of storing data that generates extra bits of

data from existing data• Virtual tape:

– Storage technology for less frequently needed dataFundamentals of Information Systems, Sixth Edition 21

Secondary Storage Devices (continued)

• Storage area network:– Uses computer servers, distributed storage devices,

and networks to tie everything together• Optical discs:

– Common form of optical disc on which data cannot be modified once it has been recorded

• Digital video disc (DVD):– Storage medium used to store software, video

games, and movies


Secondary Storage Devices (continued)

• Solid state secondary storage devices:– Store data in memory chips rather than magnetic or

optical media– Have few moving parts, so they are less fragile than

hard disk drives– Disadvantages of SSD:

• High cost per GB of data storage• Lower capacity compared to current hard drives



Input Devices

• Devices used to input general types of data:– Personal computer input devices– Speech recognition technology– Digital cameras– Touch-sensitive screens– Optical data readers– Magnetic ink character recognition (MICR) devices– Pen input devices– Magnetic stripe card– Radio Frequency Identification

Input Devices (continued)



Output Devices

• Display monitors:– Used to display the output from the computer– Plasma display:

• Uses thousands of smart cells (pixels) consisting of electrodes and neon and xenon gases that are electrically turned into plasma to emit light

– LCD displays:• Flat displays that use liquid crystals

– Organic light-emitting diodes (OLEDs):• Use a layer of organic material sandwiched between

two conductors

Output Devices (continued)

• Printers and plotters:– Two main types of printers are laser printers and

inkjet printers– Plotters are a type of hard-copy output device used

for general design work• Digital audio player:

– Can store, organize, and play digital music files• E-books:

– Digital media equivalent of a conventional printed book



Computer System Types

• Computer systems: – Can range from desktop (or smaller) portable

computers to massive supercomputers that require housing in large rooms

Computer System Types (continued)


Portable Computers• Handheld computers:

– Single-user computers that provide ease of portability because of their small size

• Laptop computer:– Personal computer designed for use by mobile users

• Notebook computers:– Lightweight computer that weighs less than 5

pounds


Portable Computers (continued)

• Netbook computer:– The smallest, lightest, least expensive member of

the laptop computer family• Tablet computers:

– Portable, lightweight computers with no keyboard• Smartphone:

– Combines the functionality of a mobile phone, camera, Web browser, e-mail tool, MP3 player, and other devices


Nonportable Single-User Computers

• Thin client:– Low-cost, centrally managed computer with no extra

drives• Desktop computers:

– Single-user computer systems that are highly versatile


Nonportable Single-User Computers (continued)

• Nettop computer:– Inexpensive desktop computer designed to be

smaller, lighter, and consume much less power than a traditional desktop computer

• Workstations:– More powerful than personal computers but still

small enough to fit on a desktop


Multiple-User Computer Systems

• Server:– Used by many users to perform a specific task, such

as running network or Internet applications• Blade server:

– Houses many computer motherboards– The approach requires much less physical space

than traditional server farms


Multiple-User Computer Systems (continued)

• Mainframe computer:– Large, powerful computer shared by hundreds of

concurrent users connected to the machine over a network

• Supercomputers:– The most powerful computers with the fastest

processing speed and highest performance


Green Computing

• Concerned with:– Efficient and environmentally responsible design,

manufacture, operation, and disposal of IS-related products

• Goals:– Reduce the use of hazardous material– Enable companies to lower their power-related costs

– Enable the safe disposal or recycling of some

700,000 tons of computers each year


Overview of Software

• Computer programs:– Sequences of instructions for the computer

• Documentation:– Describes program functions to help the user

operate the computer system• Types of software:

– Systems software– Application software


Supporting Individual, Group, and Organizational Goals

• Sphere of influence:– Scope of problems and opportunities addressed by a

particular organization• Personal sphere of influence:

– Serve the needs of an individual user• Personal productivity software:

– Helps users improve their personal effectiveness• Workgroup:

– When two or more people work together to achieve a common goal


Supporting Individual, Group, and Organizational Goals (continued)

• Workgroup sphere of influence: – Serves the needs of a workgroup

• Enterprise sphere of influence: – Supports the firm in its interaction with its

environment


Installing and Removing New Software

• Before you can use any type of software, it must be installed on a computer

• Software for personal computers typically comes on CDs or is downloaded from the Web



Systems Software

• Includes:– Operating systems– Utility programs


Operating Systems

• Set of programs that controls computer hardware and acts as an interface with application programs

• Can control one computer or multiple computers, or • Can allow multiple users to interact with one

computer• Combinations of OSs, computers, and users:

– Single computer with a single user– Single computer with multiple users– Multiple computers with multiple users– Special-purpose computers

Operating Systems (continued)



• Activities performed by the operating system:– Perform common computer hardware functions– Provide a user interface and input/output

management– Provide a degree of hardware independence– Manage system memory– Manage processing tasks– Provide networking capability– Control access to system resources– Manage files




• Common hardware functions:– Get input from keyboard or another input device– Retrieve data from disks– Store data on disks– Display information on a monitor or printer



• User interface and input/output management:– User interface:

• Allows individuals to access and command the computer system

– Command-based user interface:• Requires that text commands be given to the

computer to perform basic activities– Graphical user interface (GUI):

• Uses icons and menus displayed on screen to send commands to the computer system



• Hardware independence:– Application program interface (API):

• Allows applications to make use of the operating system

• Memory management:– Allows computer to execute program instructions

effectively and to speed processing

fundamentals of information systems, sixth edition

Documents

edition8computer systems

complexityhardware objectives

business needs

key software issues

essential hardware components

computer systemidentify

programming staffoutline

compelling business