Presentation on theme: "Introduction to the World of Computers"— Presentation transcript:
1 Introduction to the World of Computers Chapter 1:Introduction to the World of Computers
2 Computers in Your Life Why learn about computers? Pervasive computing Also known as ubiquitous computingComputers have become an integral part of our livesBasic computer literacyKnowing about and understanding computers and their uses is an essential skill today for everyone
3 Computers in Your Life Before 1980 Microcomputers in the early 80s Computers were large, expensiveVery few people had access to themComputers were mostly used for high-volume processing tasksMicrocomputers in the early 80sInexpensive personal computersComputer use increased dramaticallyTodayMore than 80% of US households include a computer, and most use computers at workElectronic devices are converging into single units with multiple capabilities
4 Computers in the Home Computers used for a variety of tasks: Looking up information and newsExchangingShopping and paying billsWatching TV and videosDownloading music and moviesOrganizing digital photographsPlaying gamesTelecommuting
5 Computers in the Home Convergence The computer has become the central part of home entertainmentDual-mode mobile phonesWireless networkingComputers can be used in nearly any locationSmart appliancesTraditional appliances with built-in computer or communication technologySmart homesHousehold tasks are monitored and controlled by a main computer in the house
6 Computers on the JobComputers have become a universal on-the-job tool for decision-making, productivity, and communicationUsed by all types of employeesUsed for access control and other security measuresUse by service professionals is growingUsed extensively by the militaryEmployees in all lines of work need to continually refresh their computer skills
7 Computers on the GoComputers are encountered in nearly every aspect of daily lifeConsumer kiosksATM transactionsPOS systems at retail storesSelf-checkout systemsPortable computers or mobile devicesM-commerce systemsGPS systems
8 What Is a Computer and What Does It Do? Computer: A programmable, electronic device that accepts data, performs operations on that data, and stores the data or results as neededComputers follow instructions, called programs, which determine the tasks the computer will performBasic operationsInput: Entering data into the computerProcessing: Performing operations on the dataOutput: Presenting the resultsStorage: Saving data, programs, or output for future useCommunications: Sending or receiving data
10 Data vs. Information Data Raw, unorganized facts Can be in the form of text, graphics, audio, or videoInformationData that has been processed into a meaningful formInformation processingConverting data into information
11 Computers Then and NowThe computer as we know it is a fairly recent inventionThe history of computers is often referred to in terms of generationsEach new generation is characterized by a major technological developmentPrecomputers and early computers (before 1946)Abacus, slide rule, mechanical calculatorPunch Card Tabulating Machine and Sorter11
12 Computers Then and Now First-generation computers (1946-1957) Enormous and powered by vacuum tubesUsed a great deal of electricity, and generated a lot of heatENIAC and UNIVACSecond-generation computers ( )Used transistorsComputers were smaller, more powerful, cheaper, more energy-efficient, and more reliablePunch cards and magnetic tape were used to input and store data
13 Computers Then and Now Third-generation computers (1964-1970) Used integrated circuits (ICs)Keyboards and monitors introducedFourth-generation computers (1971-present)Use microprocessorsIBM PC, Apple MacintoshUse keyboards, mice, monitors, and printersUse magnetic disks, flash memory, and optical disks for storageComputer networks, wireless technologies, Internet introduced
14 Computers Then and Now Fifth-generation (now and the future) Infancy stageNo precise classificationMay be based on artificial intelligence (AI)Likely use voice and touch inputMay be based on optical computers and utilize nanotechnology
15 Hardware Hardware: The physical parts of a computer Internal hardware Located inside the main box (system unit) of the computerExternal hardwareLocated outside the system unitConnect to the computer via a wired or wireless connectionThere is hardware associated with all five computer operations
17 Hardware Input devices Used to input data into the computer Keyboards, mice, scanners, cameras, microphones, joysticks, touch pads, touch screens, fingerprint readers, etc.Processing devicesPerform calculations and control computer’s operationCentral processing unit (CPU) and memoryOutput devicesPresent results to the userMonitors, printers, speakers, projectors, etc.
18 Hardware Storage devices Used to store data on or access data from storage mediaHard drives, CD/DVD discs and drives, USB flash drives, etc.Communications devicesAllow users to communicate with others and to electronically access remote informationModems, network adapters, etc.
20 SoftwareSoftware: The programs or instructions used to tell the computer hardware what to doSystem software: Operating system starts up the computer and controls its operationWithout OS computer cannot functionBoots the computer and launches programs at the user’s directionMost use a GUI to interact with the user via windows, icons, menus, buttons, etc.Windows, Mac OS, Linux, etc.
22 Application SoftwareApplication software: Performs specific tasks or applicationsCreating letters, budgets, etc.Managing inventory and customer databasesEditing photographsScheduling appointmentsViewing Web pagesSending and receivingRecording / playing CDs/DVDsDesigning homesPlaying games
23 Computer Users and Professionals Computer users (end users): People who use a computer to obtain informationComputer professionals include:ProgrammersSystems analystsComputer operations personnelSecurity specialists
24 Thin Clients and Internet Appliances Thin client or network computer (NC): Device designed to access a network for processing and data storageLower cost, increased security and easier maintenanceLimited or no local storageNot able to function as a computer if network is downInternet appliance: Specialized network computer designed for Internet access and/or exchangeOften set-top boxesCan include Internet-enabled gaming consoles
26 Midrange ServersMidrange server: A medium-sized computer used to host programs and data for a small networkUsers connect via a network with a computer, thin client, or dumb terminalMay consist of a collection of individual circuit boards called bladesVirtualization: Creating virtual environments (often used to share a server for increased efficiency)
27 Mainframe ComputersMainframe computer: Powerful computer used by several large organizations to manage large amounts of centralized dataStandard choice for large organizations, hospitals, universities, large businesses, banks, government officesLocated in climate-controlled data centers and connected to the rest of the company computers via a networkLarger, more expensive, and more powerful than midrange serversUsually operate 24 hours a dayAlso called high-end servers or enterprise-class servers
29 SupercomputersSupercomputer: Fastest, most expensive, most powerful type of computerGenerally run one program at a time, as fast as possibleCommonly built by connecting hundreds of smaller computers, supercomputing clusterUsed for space exploration, missile guidance, satellites, weather forecast, oil exploration, scientific research, complex Web sites, decision support systems, 3D applications, etc.
31 Quick Quiz1. A tablet PC is an example of a(n) _____________. a. Desktop computer b. Portable PC c. Internet appliance 2. True or False: The terms mainframe computer and supercomputer are interchangeable; both refer to the largest, most powerful computers. 3. A smartphone is an example of a(n) _____________. Answers: 1) b; 2) False; 3) mobile device
32 Computer Networks and the Internet Computer network: A collection of hardware and other devices that are connected together.Users can share hardware, software, and dataUsers can communicate with each otherNetwork servers: Manage resources on a networkClients: Access resources through the network serverComputer networks exist in many sizes and typesHome networksSchool and small business networksLarge corporatePublic wireless networksThe Internet
34 What Are the Internet and the World Wide Web? Internet: The largest and most well-known computer network in the worldIndividuals connect to the Internet using an Internet service provider (ISP)World Wide Web: One resource (a vast collection of Web pages) available through the InternetWeb sites contain Web pages stored on Web serversWeb pages viewed using a Web browser (Internet Explorer, Chrome, Safari, Firefox, Opera, etc.)A wide variety of information is available through the Web
35 Accessing a Network or the Internet Need a modem or network adapterSome networks require a username and passwordInternet connections can be:Direct (always-on) connectionsDial-up connectionsInternet addresses are used to access resources on the InternetIP address: Numeric address that identifies computers ( )Domain name: Text-based address that identifies computers (microsoft.com)Uniform resource locator (URL): Identifies Web pages (http://twitter.com/jobs/index.html)address: Identifies people for exchange
36 IP Addresses and Domain Names IP addresses are numeric and uniqueDomain names: Correspond to IP addressesTop-level domains (TLDs)identifies type of organizationor its locationCustom TLDs may soon be allowed
37 Uniform Resource Locators (URLs) URL: Uniquely identifies a Web pageConsists of:Protocol or standard being usedIdentification of the Web serverNames of folders in which the Web page file is storedWeb page’s filenameProtocols:Hypertext Transfer Protocol (http://) is typically used to display Web pages (https:// is used for secure Web pages)File Transfer Protocol (ftp://) is often used for file exchange
39 E-Mail Addresses E-mail addresses consist of: Username: A person’s identifying name for a particular domainsymbolDomain name for the computer that will be handling the person’s (mail server)Pronouncing Internet addresses