logging in or signing up 03 Hardware - Input Processing valanju Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 94 Category: Entertainment License: All Rights Reserved Like it (1) Dislike it (0) Added: December 13, 2010 This Presentation is Public Favorites: 1 Presentation Description No description available. Comments Posting comment... By: vishnu27293 (16 month(s) ago) can i down load this Saving..... Post Reply Close Saving..... Edit Comment Close By: gara_1124 (17 month(s) ago) please send me a copy to be used as reference for my lecture. thanks. Saving..... Post Reply Close Saving..... 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Edit Comment Close Premium member Presentation Transcript Principles of Information SystemsEighth Edition : Principles of Information SystemsEighth Edition Hardware: Input, Processing, and Output Devices Learning Objectives : Principles of Information Systems, Eighth Edition 2 Learning Objectives Describe how to select and organize computer hardware components to support information system (IS) objectives and business needs Describe the power, speed, and capacity of central processing and memory devices Describe the access methods, capacity, and portability of secondary storage devices Discuss the speed, functionality, and importance of input and output devices Identify popular classes of computer systems and discuss the role of each Why Learn About Hardware? : Principles of Information Systems, Eighth Edition 3 Why Learn About Hardware? Can improve productivity, increase revenue, reduce costs, and provide better service Managers are expected to know about hardware To help define business needs To ask questions and evaluate options when buying equipment Introduction : Principles of Information Systems, Eighth Edition 4 Introduction Hardware: any machinery (most of which use digital circuits) that assists in the input, processing, storage, and output activities of an information system When making hardware decisions, businesses must consider how the hardware can support: Objectives of the information system Goals of the organization Hardware Devices Analogy: A Paper-Based Office : Hardware Devices Analogy: A Paper-Based Office Principles of Information Systems, Eighth Edition 5 Secondary Storage Register Storage Output Primary Storage Input Hardware Components : Principles of Information Systems, Eighth Edition 6 Hardware Components Figure 3.1: Hardware Components Hardware Components in Action : Hardware Components in Action Execution of machine-level instruction Phase 1 : Instruction Phase – Fetch and Decode Phase 2 : Execution Phase – Execute and Store I-time: the time taken to perform phase 1 E-time: the time taken to perform phase 2 Principles of Information Systems, Eighth Edition 7 Hardware Components in Action : Principles of Information Systems, Eighth Edition 8 Hardware Components in Action Figure 3.2: Execution of an Instruction Processing and Memory Devices: Power, Speed, and Capacity : Principles of Information Systems, Eighth Edition 9 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 : Principles of Information Systems, Eighth Edition 10 Processing Characteristics and Functions Computer execute an instruction during a machine cycle Completing the instruction and execution phase – make up one machine cycle Machine cycle time is measured in: Nanoseconds (1 billionth of a second) Picoseconds (1 trillionth of a second) MIPS (millions of instructions per second) Processing Characteristics and Functions (continued) : Principles of Information Systems, Eighth Edition 11 Processing Characteristics and Functions (continued) 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 Microcode: predefined, elementary circuits and logical operations that the processor performs when it executes an instruction Physical Characteristics of the CPU : Principles of Information Systems, Eighth Edition 12 Physical Characteristics of the CPU Collection of digital circuits on chips Electrical current flows through silicon – to turn the digital circuit on or off Gordon Moore – former Intel’s chairman hypothesised that progress in chip manufacturing: transistor density of chips will double every 18 months (Moore’s Law) Physical Characteristics of the CPU (continued) : Principles of Information Systems, Eighth Edition 13 Physical Characteristics of the CPU (continued) Figure 3.3: Moore’s Law Memory Characteristics and Functions : Principles of Information Systems, Eighth Edition 14 Memory Characteristics and Functions Main memory Located physically close to the CPU, but not on the CPU chip itself Rapidly provides data and instructions to the CPU Storage Capacity : Principles of Information Systems, Eighth Edition 15 Storage Capacity Table 3.1: Computer Storage Units Types of Memory : Principles of Information Systems, Eighth Edition 16 Types of Memory Figure 3.4: Basic Types of Memory Chips Types of Memory (Cash Memory) : Principles of Information Systems, Eighth Edition 17 Types of Memory (Cash Memory) Figure 3.5: Cache Memory Multiprocessing : Principles of Information Systems, Eighth Edition 18 Multiprocessing Multiprocessing: simultaneous execution of two or more instructions at the same time Multiprocessing using coprocessors Coprocessor: speeds processing by executing specific types of instructions while the CPU works on another processing activity Parallel Computing : Principles of Information Systems, Eighth Edition 19 Parallel Computing Parallel computing: simultaneous execution of the same task on multiple processors to obtain results faster Massively parallel processing: Speeds processing by linking hundreds or thousands of processors to operate at the same time, or in parallel Each processor has its own bus, memory, disks, copy of the operating system, and applications Parallel Computing (continued) : Principles of Information Systems, Eighth Edition 20 Parallel Computing (continued) 2 different approaches to achieving parallel computing Single instruction/multiple data (SIMD) parallel processors Multiple instruction/multiple data (MIMD) parallel processors Grid computing: use of a collection of computers, often owned by multiple individuals or organizations, to work in a coordinated manner to solve a common problem Secondary Storage : Principles of Information Systems, Eighth Edition 21 Secondary Storage Permanent storage Compared with memory, offers the advantages of nonvolatility, greater capacity, and greater economy Selection of secondary storage : access methods, storage capacities, and portability required - determined by the information system’s objectives Example: credit card company Access Methods : Principles of Information Systems, Eighth Edition 22 Access Methods Two types of access methods Sequential access: records must be retrieved in order in which it’s stored Devices used are called sequential access storage devices (SASDs) Direct access: records can be retrieved in any order Devices used are called direct access storage devices (DASDs) Devices : Principles of Information Systems, Eighth Edition 23 Devices Magnetic tapes Magnetic disks Optical disks Digital video disk (DVD) Holographic Versatile Disc (HVD) Memory cards Flash memory RAID Virtual tape Magnetic Tapes : Magnetic Tapes Principles of Information Systems, Eighth Edition 24 Sequential secondary storage medium Primarily for storing backups Tapes similar to audio and videocassettes Portion of tapes are magnetized to represent bits Magnetic Disks : Magnetic Disks Principles of Information Systems, Eighth Edition 25 Direct access storage medium e.g. diskette, hard disks Allows fast data retrieval Optical Disc : Optical Disc Principles of Information Systems, Eighth Edition 26 Data is recorded by special lasers that physically burn pits in the disk. Data accessed – optical disc device (compact disk player) e.g. CD-ROM – 740MB, CD-RW DVD and HVD : DVD and HVD Principles of Information Systems, Eighth Edition 27 DVD (Digital Video Disc) Looks like a CD but more storage capacity ~ 135min of digital video. Software, video games, movies HVD (Holographic Versatile Disc) Advanced optical disk – ongoing research Hold 200GB of data Write data 10 times faster than DVD Memory cards : Memory cards Principles of Information Systems, Eighth Edition 28 Functions as a hard disk drive Portable, relatively easy to use Need to use memory card reader/writer Flash Memory : Flash Memory Principles of Information Systems, Eighth Edition 29 A silicon computer chip Keeps its memory when the power is shut off “Flash” – the memory cell is erased or reprogrammed in a single action or flash e.g. – Migo – keychain device, comes with software that captures files and settings from e-mail, word processing, web browser, presentation programs. RAID and Virtual Tape : RAID and Virtual Tape Storage technologies RAID – Redundant array of independent /inexpensive disks duplicate existing data on drives, provides exact copy, store on different physical disk drives Virtual Tape manages less frequently needed data Move data to less costly storage media Software – virtual tape server Vendor – IBM and Storage Technology Principles of Information Systems, Eighth Edition 30 Enterprise Storage Options : Principles of Information Systems, Eighth Edition 31 Enterprise Storage Options Needs to store massive amount of data 3 forms: Attached storage tape, hard disks, optical devices Simple, cost effective - single users and small groups Not allowed share storage Network-attached storage (NAS) Storage devices attach to a network Users can share and access same information Enterprise Storage Options (continued) : Principles of Information Systems, Eighth Edition 32 Enterprise Storage Options (continued) Figure 3.9: Storage Area Network (SAN) Storage area network (SAN) Special purpose, high speed network Provides direct connections between data-storage devices and computer Integrates different types of storage subsystems Input and Output Devices: The Gateway to Computer Systems : Principles of Information Systems, Eighth Edition 33 Input and Output Devices: The Gateway to Computer Systems Through input and output devices, people provide data and instructions to the computer and receive results from it Selection of input and output devices depends on organizational goals and IS objectives Characteristics and Functionality : Principles of Information Systems, Eighth Edition 34 Characteristics and Functionality Nature of data- data can be human-readable or machine-readable Data entry: converts human-readable data into machine-readable form Data input: transfers machine-readable data into system Source data automation: capturing and editing data where the data is initially created and in a form that can be directly input to a computer Input Devices : Principles of Information Systems, Eighth Edition 35 Input Devices Personal computer input devices Keyboard Mouse Speech-recognition technology Input devices that recognize human speech e.g. automate account identification process Digital cameras Terminals Input and display devices that perform data entry and input at same time Office, warehouse, factory Input Devices (continued) : Principles of Information Systems, Eighth Edition 36 Input Devices (continued) Scanning devices Optical data readers Special scanner OMR – standardized tests OCR – convert handwritten to typed doc into digital data Magnetic stripe card Swipe card Point-of-sale (POS) devices Used in retail operations to enter sales information Slide 37: Magnetic ink character recognition (MICR) devices A system for reading banking data quickly Use special ink readable by people and computers e.g. bank check Principles of Information Systems, Eighth Edition 37 Input Devices (continued) : Principles of Information Systems, Eighth Edition 38 Input Devices (continued) Automated teller machine (ATM) devices Pen input devices Touch-sensitive screens Bar-code scanners Radio Frequency Identification (RFID) Output Devices : Principles of Information Systems, Eighth Edition 39 Output Devices Display monitors Liquid crystal displays (LCDs) Organic light-emitting diodes (OLEDs) Printers and plotters Digital audio player Special-Purpose Input and Output Devices : Principles of Information Systems, Eighth Edition 40 Special-Purpose Input and Output Devices Computer-based navigation systems GPSs (Global positioning system), satellite based radio navigating system Guide to specific destination Multiple function printers Print, copy, fax,scan Eyebud screens Portable media devices Display video in front of one eye Computer System Types, Selection, and Upgrading : Principles of Information Systems, Eighth Edition 41 Computer System Types, Selection, and Upgrading Computer classification: Special-purpose computers: used for limited applications by military and scientific research groups General-purpose computers: used for a wide variety of applications Single user at a time, multiple concurrent users Computer System Types : Principles of Information Systems, Eighth Edition 42 Computer System Types Handheld computers – single user, small size, portable Portable computers – laptops, notebooks, tablet Thin client Low-cost, no extra drives, limited capabilities Desktop computers Computer System Types (continued) : Principles of Information Systems, Eighth Edition 43 Computer System Types (continued) Workstations – more powerful than personal computer, similar size to desktop, heavy mathematical computing, CAD. Servers – to perform special tasks, e.g. running network or Internet application. Computer System Types (continued) : Computer System Types (continued) Mainframe computers – large, powerful computer, shared by hundreds of concurrent users, connected via terminals Supercomputers most powerful computers, fastest processing speed, highest performance. Special purpose machines – weather forecast, military application, simulation of golf club designs. Principles of Information Systems, Eighth Edition 44 Selecting and Upgrading Computer Systems : Principles of Information Systems, Eighth Edition 45 Selecting and Upgrading Computer Systems Dispose of old equipment properly Consider factors such as speed, cost, and performance when upgrading Hard drive Main memory Printer DVD burners Summary : Principles of Information Systems, Eighth Edition 46 Summary Hardware: machinery that assists in the input, processing, storage, and output activities of an information system Hardware components: central processing unit (CPU), input and output devices, communications devices, primary storage devices, and secondary storage devices Random access memory (RAM): temporary and volatile ROM (read-only memory): nonvolatile Summary (continued) : Principles of Information Systems, Eighth Edition 47 Summary (continued) Multiprocessing: simultaneous execution of two or more instructions at the same time Sequential access: records must be retrieved in order Direct access: records can be retrieved in any order Examples of secondary storage devices: magnetic tapes and disks, DVDs, memory cards, etc. Enterprise storage options: attached storage, network-attached storage (NAS), and storage area network (SAN) Summary (continued) : Principles of Information Systems, Eighth Edition 48 Summary (continued) Examples of input devices: keyboards, mice, voice-recognition devices, terminals, scanning devices, and touch-sensitive screens Examples of output devices: display monitors, liquid crystal displays (LCDs), printers, and plotters Computers can be classified as either special-purpose or general-purpose Computer system types: handheld computers, portable computers, desktop computers, workstations, servers, etc. You do not have the permission to view this presentation. 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03 Hardware - Input Processing valanju Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 94 Category: Entertainment License: All Rights Reserved Like it (1) Dislike it (0) Added: December 13, 2010 This Presentation is Public Favorites: 1 Presentation Description No description available. Comments Posting comment... By: vishnu27293 (16 month(s) ago) can i down load this Saving..... Post Reply Close Saving..... Edit Comment Close By: gara_1124 (17 month(s) ago) please send me a copy to be used as reference for my lecture. thanks. Saving..... Post Reply Close Saving..... Edit Comment Close By: gara_1124 (17 month(s) ago) hope to get more presentation about IS, it helps me in my lecture. I will acknowledge you in my lecture. thanks. Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Principles of Information SystemsEighth Edition : Principles of Information SystemsEighth Edition Hardware: Input, Processing, and Output Devices Learning Objectives : Principles of Information Systems, Eighth Edition 2 Learning Objectives Describe how to select and organize computer hardware components to support information system (IS) objectives and business needs Describe the power, speed, and capacity of central processing and memory devices Describe the access methods, capacity, and portability of secondary storage devices Discuss the speed, functionality, and importance of input and output devices Identify popular classes of computer systems and discuss the role of each Why Learn About Hardware? : Principles of Information Systems, Eighth Edition 3 Why Learn About Hardware? Can improve productivity, increase revenue, reduce costs, and provide better service Managers are expected to know about hardware To help define business needs To ask questions and evaluate options when buying equipment Introduction : Principles of Information Systems, Eighth Edition 4 Introduction Hardware: any machinery (most of which use digital circuits) that assists in the input, processing, storage, and output activities of an information system When making hardware decisions, businesses must consider how the hardware can support: Objectives of the information system Goals of the organization Hardware Devices Analogy: A Paper-Based Office : Hardware Devices Analogy: A Paper-Based Office Principles of Information Systems, Eighth Edition 5 Secondary Storage Register Storage Output Primary Storage Input Hardware Components : Principles of Information Systems, Eighth Edition 6 Hardware Components Figure 3.1: Hardware Components Hardware Components in Action : Hardware Components in Action Execution of machine-level instruction Phase 1 : Instruction Phase – Fetch and Decode Phase 2 : Execution Phase – Execute and Store I-time: the time taken to perform phase 1 E-time: the time taken to perform phase 2 Principles of Information Systems, Eighth Edition 7 Hardware Components in Action : Principles of Information Systems, Eighth Edition 8 Hardware Components in Action Figure 3.2: Execution of an Instruction Processing and Memory Devices: Power, Speed, and Capacity : Principles of Information Systems, Eighth Edition 9 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 : Principles of Information Systems, Eighth Edition 10 Processing Characteristics and Functions Computer execute an instruction during a machine cycle Completing the instruction and execution phase – make up one machine cycle Machine cycle time is measured in: Nanoseconds (1 billionth of a second) Picoseconds (1 trillionth of a second) MIPS (millions of instructions per second) Processing Characteristics and Functions (continued) : Principles of Information Systems, Eighth Edition 11 Processing Characteristics and Functions (continued) 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 Microcode: predefined, elementary circuits and logical operations that the processor performs when it executes an instruction Physical Characteristics of the CPU : Principles of Information Systems, Eighth Edition 12 Physical Characteristics of the CPU Collection of digital circuits on chips Electrical current flows through silicon – to turn the digital circuit on or off Gordon Moore – former Intel’s chairman hypothesised that progress in chip manufacturing: transistor density of chips will double every 18 months (Moore’s Law) Physical Characteristics of the CPU (continued) : Principles of Information Systems, Eighth Edition 13 Physical Characteristics of the CPU (continued) Figure 3.3: Moore’s Law Memory Characteristics and Functions : Principles of Information Systems, Eighth Edition 14 Memory Characteristics and Functions Main memory Located physically close to the CPU, but not on the CPU chip itself Rapidly provides data and instructions to the CPU Storage Capacity : Principles of Information Systems, Eighth Edition 15 Storage Capacity Table 3.1: Computer Storage Units Types of Memory : Principles of Information Systems, Eighth Edition 16 Types of Memory Figure 3.4: Basic Types of Memory Chips Types of Memory (Cash Memory) : Principles of Information Systems, Eighth Edition 17 Types of Memory (Cash Memory) Figure 3.5: Cache Memory Multiprocessing : Principles of Information Systems, Eighth Edition 18 Multiprocessing Multiprocessing: simultaneous execution of two or more instructions at the same time Multiprocessing using coprocessors Coprocessor: speeds processing by executing specific types of instructions while the CPU works on another processing activity Parallel Computing : Principles of Information Systems, Eighth Edition 19 Parallel Computing Parallel computing: simultaneous execution of the same task on multiple processors to obtain results faster Massively parallel processing: Speeds processing by linking hundreds or thousands of processors to operate at the same time, or in parallel Each processor has its own bus, memory, disks, copy of the operating system, and applications Parallel Computing (continued) : Principles of Information Systems, Eighth Edition 20 Parallel Computing (continued) 2 different approaches to achieving parallel computing Single instruction/multiple data (SIMD) parallel processors Multiple instruction/multiple data (MIMD) parallel processors Grid computing: use of a collection of computers, often owned by multiple individuals or organizations, to work in a coordinated manner to solve a common problem Secondary Storage : Principles of Information Systems, Eighth Edition 21 Secondary Storage Permanent storage Compared with memory, offers the advantages of nonvolatility, greater capacity, and greater economy Selection of secondary storage : access methods, storage capacities, and portability required - determined by the information system’s objectives Example: credit card company Access Methods : Principles of Information Systems, Eighth Edition 22 Access Methods Two types of access methods Sequential access: records must be retrieved in order in which it’s stored Devices used are called sequential access storage devices (SASDs) Direct access: records can be retrieved in any order Devices used are called direct access storage devices (DASDs) Devices : Principles of Information Systems, Eighth Edition 23 Devices Magnetic tapes Magnetic disks Optical disks Digital video disk (DVD) Holographic Versatile Disc (HVD) Memory cards Flash memory RAID Virtual tape Magnetic Tapes : Magnetic Tapes Principles of Information Systems, Eighth Edition 24 Sequential secondary storage medium Primarily for storing backups Tapes similar to audio and videocassettes Portion of tapes are magnetized to represent bits Magnetic Disks : Magnetic Disks Principles of Information Systems, Eighth Edition 25 Direct access storage medium e.g. diskette, hard disks Allows fast data retrieval Optical Disc : Optical Disc Principles of Information Systems, Eighth Edition 26 Data is recorded by special lasers that physically burn pits in the disk. Data accessed – optical disc device (compact disk player) e.g. CD-ROM – 740MB, CD-RW DVD and HVD : DVD and HVD Principles of Information Systems, Eighth Edition 27 DVD (Digital Video Disc) Looks like a CD but more storage capacity ~ 135min of digital video. Software, video games, movies HVD (Holographic Versatile Disc) Advanced optical disk – ongoing research Hold 200GB of data Write data 10 times faster than DVD Memory cards : Memory cards Principles of Information Systems, Eighth Edition 28 Functions as a hard disk drive Portable, relatively easy to use Need to use memory card reader/writer Flash Memory : Flash Memory Principles of Information Systems, Eighth Edition 29 A silicon computer chip Keeps its memory when the power is shut off “Flash” – the memory cell is erased or reprogrammed in a single action or flash e.g. – Migo – keychain device, comes with software that captures files and settings from e-mail, word processing, web browser, presentation programs. RAID and Virtual Tape : RAID and Virtual Tape Storage technologies RAID – Redundant array of independent /inexpensive disks duplicate existing data on drives, provides exact copy, store on different physical disk drives Virtual Tape manages less frequently needed data Move data to less costly storage media Software – virtual tape server Vendor – IBM and Storage Technology Principles of Information Systems, Eighth Edition 30 Enterprise Storage Options : Principles of Information Systems, Eighth Edition 31 Enterprise Storage Options Needs to store massive amount of data 3 forms: Attached storage tape, hard disks, optical devices Simple, cost effective - single users and small groups Not allowed share storage Network-attached storage (NAS) Storage devices attach to a network Users can share and access same information Enterprise Storage Options (continued) : Principles of Information Systems, Eighth Edition 32 Enterprise Storage Options (continued) Figure 3.9: Storage Area Network (SAN) Storage area network (SAN) Special purpose, high speed network Provides direct connections between data-storage devices and computer Integrates different types of storage subsystems Input and Output Devices: The Gateway to Computer Systems : Principles of Information Systems, Eighth Edition 33 Input and Output Devices: The Gateway to Computer Systems Through input and output devices, people provide data and instructions to the computer and receive results from it Selection of input and output devices depends on organizational goals and IS objectives Characteristics and Functionality : Principles of Information Systems, Eighth Edition 34 Characteristics and Functionality Nature of data- data can be human-readable or machine-readable Data entry: converts human-readable data into machine-readable form Data input: transfers machine-readable data into system Source data automation: capturing and editing data where the data is initially created and in a form that can be directly input to a computer Input Devices : Principles of Information Systems, Eighth Edition 35 Input Devices Personal computer input devices Keyboard Mouse Speech-recognition technology Input devices that recognize human speech e.g. automate account identification process Digital cameras Terminals Input and display devices that perform data entry and input at same time Office, warehouse, factory Input Devices (continued) : Principles of Information Systems, Eighth Edition 36 Input Devices (continued) Scanning devices Optical data readers Special scanner OMR – standardized tests OCR – convert handwritten to typed doc into digital data Magnetic stripe card Swipe card Point-of-sale (POS) devices Used in retail operations to enter sales information Slide 37: Magnetic ink character recognition (MICR) devices A system for reading banking data quickly Use special ink readable by people and computers e.g. bank check Principles of Information Systems, Eighth Edition 37 Input Devices (continued) : Principles of Information Systems, Eighth Edition 38 Input Devices (continued) Automated teller machine (ATM) devices Pen input devices Touch-sensitive screens Bar-code scanners Radio Frequency Identification (RFID) Output Devices : Principles of Information Systems, Eighth Edition 39 Output Devices Display monitors Liquid crystal displays (LCDs) Organic light-emitting diodes (OLEDs) Printers and plotters Digital audio player Special-Purpose Input and Output Devices : Principles of Information Systems, Eighth Edition 40 Special-Purpose Input and Output Devices Computer-based navigation systems GPSs (Global positioning system), satellite based radio navigating system Guide to specific destination Multiple function printers Print, copy, fax,scan Eyebud screens Portable media devices Display video in front of one eye Computer System Types, Selection, and Upgrading : Principles of Information Systems, Eighth Edition 41 Computer System Types, Selection, and Upgrading Computer classification: Special-purpose computers: used for limited applications by military and scientific research groups General-purpose computers: used for a wide variety of applications Single user at a time, multiple concurrent users Computer System Types : Principles of Information Systems, Eighth Edition 42 Computer System Types Handheld computers – single user, small size, portable Portable computers – laptops, notebooks, tablet Thin client Low-cost, no extra drives, limited capabilities Desktop computers Computer System Types (continued) : Principles of Information Systems, Eighth Edition 43 Computer System Types (continued) Workstations – more powerful than personal computer, similar size to desktop, heavy mathematical computing, CAD. Servers – to perform special tasks, e.g. running network or Internet application. Computer System Types (continued) : Computer System Types (continued) Mainframe computers – large, powerful computer, shared by hundreds of concurrent users, connected via terminals Supercomputers most powerful computers, fastest processing speed, highest performance. Special purpose machines – weather forecast, military application, simulation of golf club designs. Principles of Information Systems, Eighth Edition 44 Selecting and Upgrading Computer Systems : Principles of Information Systems, Eighth Edition 45 Selecting and Upgrading Computer Systems Dispose of old equipment properly Consider factors such as speed, cost, and performance when upgrading Hard drive Main memory Printer DVD burners Summary : Principles of Information Systems, Eighth Edition 46 Summary Hardware: machinery that assists in the input, processing, storage, and output activities of an information system Hardware components: central processing unit (CPU), input and output devices, communications devices, primary storage devices, and secondary storage devices Random access memory (RAM): temporary and volatile ROM (read-only memory): nonvolatile Summary (continued) : Principles of Information Systems, Eighth Edition 47 Summary (continued) Multiprocessing: simultaneous execution of two or more instructions at the same time Sequential access: records must be retrieved in order Direct access: records can be retrieved in any order Examples of secondary storage devices: magnetic tapes and disks, DVDs, memory cards, etc. Enterprise storage options: attached storage, network-attached storage (NAS), and storage area network (SAN) Summary (continued) : Principles of Information Systems, Eighth Edition 48 Summary (continued) Examples of input devices: keyboards, mice, voice-recognition devices, terminals, scanning devices, and touch-sensitive screens Examples of output devices: display monitors, liquid crystal displays (LCDs), printers, and plotters Computers can be classified as either special-purpose or general-purpose Computer system types: handheld computers, portable computers, desktop computers, workstations, servers, etc.