cxc information technology section one revision does not include binary arithmetic & information...
TRANSCRIPT
CXC Information CXC Information Technology Technology Section One RevisionDoes not include binary arithmetic & Information Processing (Unit 5)
What you’ll need
•Past paper questions: 2010 – 2014•Mr. Alleyne website: www.it.anthonyalleyne.com•Constant revision is critical
Unit One - Basic Unit One - Basic componentscomponentsCPU: ALU and control unitPrimary Storage: RAM, ROM
etc.Secondary Storage: diskettes,
CDs etc.Input devices: mouse etc.Output devices: monitor etc.
Primary MemoryPrimary MemoryBistable device: Only has two
states, on and off (1 and 0)Read Only Memory: boots up the
PC. Non volatileRandom Access Memory: used
while PC is working. Volatile (needs power)
PROM: Programmable ROMEPROM: Erasable programmable
ROM
Secondary memorySecondary memoryMagnetic tape: uses sequential
access. Good for backing upFloppy disk: uses direct access. Hard disk (drive): fixed or moving
headOptical disk: CD / DVDMemory cards: Cameras, phones
etc.USB (flash) drives: Portable
USB – Universal Serial Bus
Other termsOther termsTrack: Circles around disk’s surfaceSector: One part of the circleCluster: Adjacent sectorsBuffer: extra memory space when
copying dataSequential access: data stored in
the order it’s receivedDirect access: data stored in any
orderHard drive interfaces
◦SCSI, IDE, SATA and USB (external hard drive)
Units of storageUnits of storageBit: smallest unit of storageByte: 8 bitsKilobyte: 1024 bytesMegabyte: 1024 kilobytesGigabyte: 1024 megabytesTerabyte: 1024 gigabytesWord / Word size: size of a single
instruction. (i.e. How much data a CPU can handle at one time.)
Input DevicesInput DevicesMouseKeyboardJoystickMicrophoneScannerWebcamGraphics
pad/tabletBarcode readerWebcam
Light PenTouch terminalOptical Mark
ReaderOptical Character
Reader Magnetic Ink
Character ReaderBiometric SystemSensor
Output DevicesOutput Devices
MonitorProjectorSpeakersHeadphone
sPrintersPlotterMicrofilm
Output termsOutput termsResolutionPixelQualityHard copySoft copyHuman readableMachine readable
PrintersPrintersDot matrixLineDaisy Wheel
InkjetLaserjetThermal
IMPACT
NON -IMPACT
SoftwareSoftwareApplication Software
◦Custom written (for one purpose only)◦Specialised (for a group/category:
ACCPAC)◦General purpose (for everyone: Word, etc.)◦Integrated (more than one programme:
Office)
Systems software◦Operating system (Windows, Linux, Unix,
OSX)
Operating System Operating System functionsfunctionsFile managementResource management User managementInput – Output managementSecurity Memory Maintenance (defrag, format,
cleanup)
Interfaces and termsInterfaces and termsCommand line interface: command
must be typed. Difficult to use
Menu driven interface: command selected from a menu: Options limited
Graphical user interface: Like Windows
Pop up and pull down menusIconsTaskbar
Processing – how does the Processing – how does the CPU do it?CPU do it?
Batch: collect in groups, then
process
Online: processed once CPU is on
Real-time: processed immediately
Timesharing: processes many
jobs, a piece at a time
Computer specificationsComputer specificationsCPU: 2.4 Ghz 64-bit Pentium 4Hard drive: 1TB 7200 rpm SATAMemory: 1GB DDR-RAMOS: Windows 7 Home editionPorts: 6 USB ports, 1 firewire portOptical drive: 54X DVD/RW driveSlots: 1 AGP slotVideo: Radeon 64MB video card
Networks Networks Local area network: small areaMetropolitan area network:
medium sized areaWide area network: large area
(e.g. continent)
Internet: public Intranet: privateExtranet: private with some outside
access
Networking termsNetworking termsCoaxial cable
(antenna)Twisted pair
(phone/ADSL)Fiber optic cable
(light)
InfraredBluetoothWi-fiHotspot
Bandwidth (how much)Speed / Rate (how fast)
Voiceband (phone line)Broadband (ADSL)Wireless
Simplex (1 way only)Half duplex (1 way at a
time)Full duplex (both ways)
The internet & termsThe internet & termsWWWWeb page, site,
browserHTTP, HTMLFTPURLUpload vs.
downloadSearch engineIRC
E-mailBulletin boardNewsgroupBloggingE-commerceE- learningVoIP
Data SecurityData SecurityPasswordsEncryptionAccess
restrictionsFirewallsVirus protectionBackup &
recoveryArchiving
LocksSecurity guardsFireproof
cabinetsWaterproof
cabinetsBiometric
systems
Data misuseData misuseInformation TheftCopyright infringementEavesdroppingInvasion of privacyComputer fraudPropaganda
Current trendsCurrent trendsExpert SystemsComputer Aided Manufacturing
(and Design)TeleconferencingTelemarketingRobotsLaser technology
JobsJobs
TechnicianSoftware / computer engineerDatabase / Network
administratorFile librarianWeb master / web developerSoftware trainer (teacher)Systems analystProgrammers
Information ProcessingInformation Processing
Anyone can use computers for the following
CommunicationResearchPublishing and PrintingStorageData processing and analysis