Kĩ thuật lập trình - Introduction to information technology

1Introduction to Information TechnologyYour Digital WorldChapter1McGraw-Hill/Irwin© 2007 The McGraw-Hill Companies, Inc. All rights reserved.1-2Why become computer savvy?Know what computers can do for youKnow the limitations of computersKnow how computers can harm youKnow how to solve computer problemsKnow when & how to get helpDiscussion Question: What was your worst computer problem?3IT & Your Life: The Future NowDefinition: Information Technology (IT) describes any technology that helps to produce, manipulate, store, communicate, and/or disseminate informationPart 1: Computer TechnologyPart 2: Communication TechnologyDiscussion Question: How many times today did YOU use one of these technologies?4How is IT being used in Education?99% of schools have internet access85% of college students own their own computer¾ of college students use the internet 4 or more hours per week½ of all college professors require students to use email in their classesMany college classes are either taught online or have a class websiteDefinition: Distance Learning is online educationDiscussion Question: Have you ever used the computer in your classroom for something other than the work in that class?5Rules for Computers in ClassroomsProblem: Computers in the classroom can be used or misused.What should they be used for?Following the lecture slidesWorking along with the instructorPerforming instructor-assigned internet searchesCompleting assignments for this classWhat is misuse?Text messaging or emailing friendsSurfing the internet for entertainmentDoing assignments for other classes6Health: High Tech for WellnessTelemedicine: Medical care via telecommunications lets doctors treat patients from far away3D Computer models allow accurate tumor location inside a skullRobots permit precise microsurgeryHandheld computers allow patients to measure blood sugarMedical implants allow stroke patients to directly control computers to talk for themHealth websites provide medical information7Money: Cashless Society?Definition: Virtual means something that is created, simulated, or carried on by means of a computer or a computer networkVirtual airline ticketsVirtual money Online bill payingPayPalElectronic payroll depositMicropayments for online musicDiscussion Question: How important is security if all your money is virtual?8Leisure: Infotech in Entertainment & the ArtsVideogamesDownloadingMoviesMusicTerm papers????Ethical/legal questionsMost movies use computer animationDigital editing9IT in Government & DemocracyGovernments can’t control informationIndividuals can find multiple viewpoints on internetEmail makes it easier to contact the governmentCompeting websites promote & criticize politicianswww.whitehouse.govwww.whitehouse.orgBlogs are a tool for political candidates10Jobs & CareersHotels: Desk clerks use computerized reservations systemsLaw Enforcement: Officers use computersOn patrolTo check stolen carsTo check criminal recordsTo check arrest warrantsEntertainment: Office uses like budgets, payroll, ticketingAlso virtual set design, 3-D animation, special effects11Jobs & CareersOffice careers: Budget, payroll, letter-writing, emailTeaching: Automated grading systems, emailing parentsFashion: Sales/inventory control systems, ordering, personnelJob-hunting: Use word processor to create resumesPost resumes onlineOnline job searchesDiscussion Question: Can anyone think of a career that does NOT require computer skills?12The Telephone Grows Up1973: First cellphone call2006: Nokia estimates 2 billion mobile phone subscribersToday’s cellphones:Are mobileCan take and send picturesCan connect to the internetCan send and receive text messages Discussion Question: Why are cellphones banned in high-security military bases?13Internet, World Wide Web, & CyberspaceInternetThe worldwide computer networkLinks thousands of smaller networksLinks educational, commercial, military entities, and individualsOriginally developed to share only text and numeric data14Internet, World Wide Web, & CyberspaceWorld Wide WebThe multimedia part of the internetAn interconnected system of servers that support specially formatted documents in multimedia formIncludes text, still images, moving images, soundResponsible for the growth and popularity of the internet15Internet, World Wide Web, & CyberspaceCyberspaceTerm coined by William Gibson in Neuromancer (1984)Described a futuristic computer network people “plugged” into directly with their brainsNow means The webChat rooms Online diaries (blogs)The wired and wireless communications world16Email TipsAlways put a subject line in your messageFor short messages, that’s all you needSend attachments only when necessaryEvery recipient gets a copy – For 500 people that’s 500 copies!For a short attachment, copy the text to the email itself instead of sending the attachmentDon’t open attachments unless you know the senderIt could contain a virus or malware17Email TipsUse discretion about sending emailsEmails aren’t secretThey can be easily forwarded to othersCheck grammar, spelling to bosses, customersDon’t use email to express criticism or sarcasmEmail received at work is the property of your employerDeleting email messages does not remove them everywhereDon’t neglect real personal contact185 Computer TypesSupercomputersPriced from $1 million to $350 millionHigh-capacity machines with thousands of processorsMulti-user systemsTo learn more about one, go to ComputersWorkstationsMicrocomputersMicrocontrollers195 Computer TypesSupercomputersMainframe ComputersUntil late 1960’s, the only computer availableCost $5,000 - $5 millionMulti-user systems; accessed using a terminalTerminals only have a keyboard and monitor; can’t be used aloneTo see one, go to Computer TypesSupercomputersMainframe ComputersWorkstationsIntroduced in early 1980sExpensive, powerful personal computersUsed for scientific, mathematical, engineering, computer-aided design (CAD), computer-aided manufacturing (CAM)A less-expensive alternative to mainframesTo see some examples with current pricing, go to Computer TypesSupercomputersMainframe ComputersWorkstationsMicrocomputersPersonal computers that cost $500 to $5000Used either stand-alone or in a networkTypes include: desktop, tower, notebooks, or Personal Digital Assistants (PDAs)Microcontrollers225 Computer TypesSupercomputersMainframe ComputersWorkstationsMicrocomputersMicrocontrollersAlso called embedded computersTiny, specialized microprocessors inside appliances and automobilesThey are in: microwaves, programmable ovens, blood-pressure monitors, air bag sensors, vibration sensors, MP3 players, digital cameras, e-pliances, keyboards, car engine controllers, etc.Discussion Question: Now, how many of you would say you have NOT used a computer today?23 ServersAre central computersMay be any of the 4 larger computer types.“Server” describes a functionHold data (databases) and programsConnect to and supply services for clientsClients are other computers like PCs, workstations, other devices 24Understanding Your Own Computer3 key conceptsPurpose of a computerTurn data into informationData: the raw facts and figuresInformation: data that has been summarized and manipulated for use in decision makingHardware vs. SoftwareHardware is the machinery and equipment in the computerSoftware is the electronic instructions that tell the computer how to perform a task25Understanding Your Own Computer3 key concepts (continued)The basic operationsInput: What goes in to the computer systemProcessing: The manipulation a computer does to transform data into informationStorage: Temporary storage: Memory is primary storagePermanent storage: Disks and media such as DVDs and CDs are secondary storageOutput: What comes out Numbers or pictures on the screen, printouts, soundsCommunications: Sending and receiving data26Building Your Own PCWhat would you need?Keyboard & MouseInside the system cabinetCase and power supplyProcessor chip – the Central Processor Unit (CPU)Memory chips – Random Access Memory (RAM)Motherboard – the system boardMemory chips plug inProcessor chip plugs inMotherboard attaches to system cabinetPower supply is connected to system cabinetPower supply wire is connected to motherboardStorage Hardware: Floppy, Hard Drive, Zip, CD/DVD, USB27Building Your Own PCStorage Hardware: Floppy, Hard Drive, Zip, CD/DVD, USBStorage capacity is represented in bytes1 byte = 1 character of data1 kilobyte = 1,024 characters1 megabyte = 1,048,576 characters1 gigabyte = over 1 billion characters1 terabyte = over 1 trillion characters1 petabyte = about 1 quadrillion charactersPermanently installed: floppy drives, hard drives, Zip drives, CD/DVD drives, USB portsRemovable media: floppy disks, Zip disks, CDs, DVDs, flash drives28Building Your Own PCOutput hardwareVideo and sound cardsMonitorSpeakersPrinterJoystickCommunications hardwareModem (internal or external)Network Card29SoftwareSystem Software (Operating System)Must be installed before application softwareOperating System (OS) options for the PCLinuxWindowsUnixOperating System (OS) options for the MacMac OSApplication SoftwareInstall after the OSApplication depends on OS, for exampleLinux applications won’t work on WindowsWindows applications won’t work on Linux30Future of Information Technology3 directions of Computer DevelopmentMiniaturizationSpeed Affordability3 directions of Communications DevelopmentConnectivityInteractivityMultimedia31Convergence, Portability, & PersonalizationConvergence: the combination ofComputersConsumer electronicsEntertainmentMass mediaPortabilityCollaboration: software that allowsPeople to share anything instantlyPeople to enhance the information as they forward it32EthicsDefinition: Ethics is the set of moral values or principles that govern the conduct of an individual or groupIs ethics relevant for Information Technology?Let’s revisit the discussion question from slide 1-7How important is ethics if all your personal information, health information, AND virtual money is stored on computers? Would YOU trust a physician who downloaded his/her term papers from the Internet?33