4 Microcomputer Systems Called a personal computer or PCComputing power now exceeds that of the mainframes of previous generationsRelatively inexpensiveDesktop, Hand-held, notebook, laptop, tablet, portable, and floor-standingHome , personal , professional , workstation or multiuser systems.
6 Microcomputer Systems Workstations- Supports heavy mathematical computing and graphics display demandsEx:- CAD in engineering, - Portfolio analysis.Network Servers- More powerful than workstations- Coordinates telecommunications and resource sharing- Supports LAN and Internet.
7 TerminalsTerminal: is any input/output device connected by a network to a computer.Types:Dumb terminals: keyboard and video monitor with limited processing capabilities.Intelligent terminals: networked PCs that perform data entry and other information processing tasks.Transaction terminals:Use keyboards, touch screen, bar code scanners to capture data , while relying on servers in the network for further transaction processing.ex in banks, ATMs machines, airport check-in, POS.Dumb terminals are being phased out for more intelligent terminals
8 Terminals Network terminals: Windows terminals: depend on network servers for Windows software, processing power and storage.Internet terminals: depend on the Internet/Intranet servers for their operating systems and application software.
9 Information Appliances Hand-held microcomputer devices, known as personal digital assistants (PDAs).Web-enabled PDAs use touch screens, pen-based handwriting recognition, or keypads.Mobile workers use to access or the Web, exchange data with desktop PCs or Web servers.Latest entrant is the RIM BlackBerry, Apple iPhone.Information Appliances may also take the form of:Video-game consoles and other devices that connect to your home television set. Enable you to surf the WWW, , play.Telephone-based home appliances that access the web.
10 Midrange SystemsHigh-end network servers that handle large-scale processing of business applications.Not powerful as mainframes.Less expensive to buy, operate, maintain than mainframes.First became popular as minicomputers for scientific research and industrial process monitoring.Today used in:Computer-aided manufacturing (CAM).Used as front-end servers to assist mainframes in telecommunications processing and network management.
11 Mainframe Computer Systems Large, fast, powerful computer systemsLarge primary storage capacity.High transaction processingHandles complex computationsUsed to:Handle the information processing of major corporation and government agencies with high transaction processing.As a superservers for the large client/server networks and high- volume Internet websites for large companies.Becoming a popular computing platform for: Data mining, warehousing, electronic commerce applications
12 Supercomputer Systems Extremely powerful computer systems designed for scientific, engineering and business applications requiring extremely high speeds for massive numeric computations.Markets for supercomputers include:Government research agencies.Large universities.Major corporations.Used for global weather forecasting, military defense, astronomy.Billions to trillions of operations per second.Millions of dollars.
13 The Computer System Concept A computer system is an interrelated combination of components performing basic functions to provide end users with a powerful information processing tool.InputControlComputerSystemProcessingStorageOutput
15 Computer Processing Speeds Early computersMilliseconds (thousandths of a second)Microseconds (millionths of a second)Current computersNanoseconds (billionth of a second)Picoseconds (trillionth of a second)Program instruction processing speedsMegahertz (millions of cycles per second)Gigahertz (billions of cycles per second)Commonly called “clock speed”
16 PeripheralsPeripheralGeneric name for all input, output, and secondary storage devicesDepend on direct connections to the CPU of a computer systemAll online devicesOnline DevicesSeparate from the CPU, but electronically connected to (and controlled by) itOffline DevicesSeparate from, and not under the control of, the CPU
18 Input Technologies Pointing Devices: Common input devices: Keyboard. Examples:Electronic mouse and trackball.Pointing stickTouch pad.Touch screen.
19 Pen-Based Computing Pen-Based: Used in Tablet PCs and PDAs They have a Pressure-sensitive layer, similar to touch screen, under liquid crystal display (LCD) screen.Software digitizes handwriting, and hand drawing.Examples: Graphics Tablet, Digitizer.
20 Speech Recognition Systems Speech may be the future of data entry because it’s the easiest, most natural means of human communication.Recognizing speech patterns:Discrete speech recognition: requires pauses between each word.Continuous speech recognition (CSR) recognizes continuous speech.
21 Speech Recognition Software Speech recognition systems digitize, analyze, and classify your speech and its sound patterns:Compares your speech patterns to a database of sound patternsPasses recognized words to your softwareSpeech recognition SW requires voice recognition trainingSpeaker-independent voice recognition systems:Allow computers to recognize words from a voice never heard beforeUsed in voice-messaging computers, computerized telephone call switching.
22 Optical scanner, copier, fax & printer Optical ScanningSheet-fed scannerFlatbed scannerOptical scanner, copier, fax & printerDevices read text or graphics and convert them into digital computer input.Enables direct entry of data from source documents into a computer system.Document management library systemScans documents, then organizes and stores them for easy reference or retrieval.
23 Optical Scanning Scanners Optical Character Recognition (OCR) Compact desktop models are popular for low cost and ease of useLarger, more expensive flatbed scanners are faster, offer high-resolution color scanningOptical Character Recognition (OCR)Software that reads characters and codesUsed to read product labels, airline tickets, score tests, read bar codes
24 Other Input Technologies Magnetic stripeRead magnetic stripe on credit cardsSmart cardsMicroprocessor chip and memory .Digital camerasDigital Camcorder.Magnetic Ink Character Recognition (MICR)Identification numbers of bank and account printedin magnetic ink on bottom of check.
25 Output Technologies Voice Response Video Displays Printed Output Increasingly found along with video displays in business applicationsVideo DisplaysCathode-ray tube (CRT)Liquid crystal display (LCD)Plasma displaysPrinted OutputInkjet , laser, multifunction model
26 Computer Storage Fundamentals Data processed & stored in computer systems through presence or absence of signals , Either ON or OFFUses two-state binary data representationOn (1) or Off (0)Smallest element of dataBitEither 0 or 1Group of eight bits, which operate as a single unitByteRepresents one character or number
29 Direct (Random) and Sequential Access Direct Access or Random AccessDirectly store and retrieve data.Each storage position has unique address and can be accessed in same length of time.Semiconductor memory chips, magnetic disks.Sequential AccessData is stored and retrieved in a sequential process.Must be accessed in sequence by searching through prior data.Magnetic tape.Direct or Random AccessDirectly store and retrieve dataEach storage position has a unique address and can be accessed in the same length of timeSemiconductor memory chips, magnetic disksSequential AccessData is stored and retrieved sequentiallyMust be accessed in sequence by searching through prior dataMagnetic tape
30 Semiconductor MemoryThe primary storage (main memory) of your computer consists of microelectronic “semiconductor memory “chips.It provides you with the working storage your computer needs to process your applications.Advantages: small size, fast, shock and temperature resistanceDisadvantages: volatility; must have uninterrupted electric power or the contents of the memory will be lost. or permanently “burn in” the contents so they cannot be erased by a loss of power.
31 Types of Semiconductor Memory Random Access Memory (RAM)Read-Only Memory (ROM)Flash Drives“Jump Drive”1. Most widely used primary storage medium2. Volatile memory3. Read/write memory1. Permanent storage2. Can be read, but not overwritten3. Frequently used programs (parts of OS) burned into the chips during manufacturing4. Called firmwareNew type of permanent storage, can store data for unlimited periods without power.Easily transportedPlugs into any USB port.
32 Hard Disk Drives & Floppy Disks (diskettes) Magnetic DisksUsed for secondary storageFast access and high capacityReasonable costTypes of Magnetic Disks:Floppy disksA single magnetic disk inside a plastic jacketHard disk drivesMagnetic disks, access arms, and read/write heads in sealed module.Hard Disk Drives & Floppy Disks (diskettes)Floppy disk contains 1.44 MegabytesZip drive (similar to floppy disk) up to 750 MBHard disks can contain hundreds of GB of storage
33 Magnetic Disks RAID (Redundant arrays of independent disks) Disk arrays of interconnected hard disk drives.They combine from 6 to more than 100 hard disk drives into a single unit.Provide large capacities (1-2 TB or more).Provide fault tolerant with multiple copies on several disksStorage area networks (SANs) are highspeed fiber channel local area networks thatcan interconnect many RAID units and thusshare their capacity through network serverswith many users.
34 Magnetic Disks Magnetic Tape: Tape ReelTape CartridgeMagnetic Tape:Include Tape reels, and cartridges (larger capacity).Lower-cost storage solutionUsed for: long term archival and backup storage
36 Uses of Optical Disks in Business Image ProcessingLong-term storage of historical image filesStorage of scanned documentsPublishing MediumAllows fast access to reference materialsCatalogs, directories ,manuals and so onInteractive Multimedia Applications in businessMultimedia encyclopedias, Video games, educational videos, and so on