CHAPTER 9multitasking provides process and memory management services that allow two or more tasks, jobs, or programs to run simultaneously multithreading allows multiple parts, or threads, to run simultaneously within a single program multiprocessing capability supports a division of labor among all the processing units memory leak when an application requests memory but never releases it, can cause an application not to function properly single-user operating system Deals with one set of input devices those that can be controlled by one user at a time, such as OS for tablets and smartphones. multiuser operating system Allows a single, centralized computer to deal with simultaneous input, output, and processing requests from many users. server operating system Provides tools for managing distributed networks, email servers, and Web hosting sites. Server operating systems typicalling route data and programs to each user's local computer where the actual processing takes place. desktop operating system Designed for desktop or laptop personal computer. The computer you use at home, school, or at work is most likely configured with a desktop operating system, such as Microsoft Windows or Mac OS. Today's desktop operating systems invariably provide multitasking capabilities so that users can run more one application at a time. mobile operating system Designed for devices such as smartphones and tablets. Mobile OSs support touchscreens, but tend to limit multitasking and user access to local storage devices. kernel Provides essential operating system services, such as memory management and file access. The kernel stays in RAM all the time your computer is on. boot process The sequence of events that occurs between the time that you turn on a computer and the time that it is ready for your to issue commands. bootstrap program Built into special ROM circuitry housed in the computer's system unit. When you turn on a computer the ROM circuitry power receives power and begins the boot process by executing the bootstrap program. user interface The combination of hardware and software that helps people and computers communicate with each other. command-line interface Originally computers had a ____ that required users to type memorized commands to run programs and accomplish tasks. graphical user interface (GUI) Provides a way to select menu options and manipulate graphical objects displayed on the screen using a mouse or gesture. desktop A visual work area that covers the entire screen and remains in the background throughout a computing sesion. taskbar or dock A desktop includes a ___ or ____ for launching applications. application windows Launched applications are displayed here on the desktop which can be resized and repositioned. start screen Popular on handheld devices, appears at the end of the boot process whenever it is invoked by the user, commonly by pressing the Home button. Start screen display icons or tiles for apps, so that you can select the one you want to use. icon or tile Small picture that represents a program, file, or hardware device. Some icons are designed as tiles, which can display information feeds of live data. menu / menu bar Displays a list of commands or options. Menus were developed in response to difficulties many people experienced trying to remember command words and syntax for commands line user interfaces. ribbon Alternative type of menu that is arranged as rows of tools on a succession of tabs. Microsoft pioneered the ribbon interface element, which was incorporated in the last several editions of Microsoft Office. submenu Additional set of commands that the computer displays after you make a selection from the main menu. Sometimes a submenu displays after another submenu. dialog box Displays the options associated with a command. DOS (Disk Operating System) The first PCs used a command-line OS called ____. Windows RT Designed as a mobile OS for tablet devices with ARM processors. Mac OS Macintosh Operating System, Apple's computer systems. Uses the "dock." dual boot Software called Boot Camp is a ____ ____ utility that can switch between Mac OS X or Windows. To change operating systems, you have to reboot. virtual machine Allow you to use one computer to simulate the hardware and software of another. Each virtual machine has its own simulated processor (or core processor), RAM, video card, input and output ports, and OS. Each machine can run most software that's compatible with the virtual OS platform. Popular virtual machine software such as VMware and Parallels Desktop can run on most computers with Intel microprocessors, including Intel Macs, PCs, and generic Linux computers data fork Similar to files in other operating systems. It contains data, such as the text for a document, the graphics for a photo, or the commands for a program. resource fork Companion file that stores information about the data in the data fork, such as the file type and the application that created it. iOS Operating system for the Apple iPhone, which launched in 2007. Used for the iPod Touch and iPad. All iOS devices use ARM-based microprocessors. Android Mobile operating system that is a popular platform for tablet computers, smartphones, and ebook readers. It is an open source OS under the project leadership of Google. Designed for ARM processors. UNIX Operating system was developed in 1969 at AT&T's Bell Labs. Dependable in multiuser environments. Linux Operating system distributed along with its source code under the terms of a GPL (General Public License). A Linux distribution is a download that contains the Linux kernel, system utilities, graphical user interface, applications, and an installation routine. Linux distribution Download that contains the Linux kernel, system utilities, graphical user interface, applications, and an installation routine. Beginner-friendly Linux distributions include Fedora, Mint, Debian, openSUSE, and Ubuntu. Blackberry OS Is a proprietary operating system produced by RIM. Key feature is the ability to work with corporate e-mail software systems produced by Microsoft and IBM. push technology RIM pioneered push technology, in which notifications are automatically sent to a device. file-naming conventions You must adhere to file-naming conventions when saving files:Case sensitivity, Maximum length, Spaces allowed, Numbers allowed, Characters not allowed, File names not allowed. file extension Sometimes referred to as a file name extension; is an optional file identifier that is seperated from the main file name by a period. Example: paint.exe File extensions provide clues to a file's contents .exe (Windows) and .app (Mac OS). A file extension does not really define the format of a file. reserved words Used as commands or special identifiers. You cannot use these alone as a file name. file location To designate a file's location, you must first specify the device where the file is stored. The main hard disk usually is referred to as drive C. Macs do not use drive letters. disk partition A section of hard disk drive that is treated as a separate storage unit. Partitions can be assigned drive letters. Partitions are not the same as folders. directory Every storage device has a ____ containing a life of its files. root directory The main directory is referred to as the root directory. On a a PC, the root directory is identified by the device letter followed by a backslash. Example: the root directory of the hard disk would be C:\ subdirectory A root directory can be subdivided into smaller lists. folder When using Windows, Mac, or a Linux graphical file manager, each subdirectory is depicted as a folder file specification (path) A computer's file location. Example on a PC C:\Music\iTunes\iTunes Media\Music\Gee.mp3 file format Refers to the organization and layout of data that is stored in a file. The format of a file usually includes a header, data, and possibly an end-of-file marker. Example of graphical file formats: GIF, JPEG, PNG. file header Section of data at the beginning of a file that contains information about a file, such as the date it was created, the date it was last updated, its size, and its file type. native file format A software application can open files that exist in its native file format, plus several other file formats. Example: Microsoft Word opens files in its native .docx as well as HTML (.htm or .html), Text (.txt), and Rich Text Format (.rtf) file tag Describes the file's contents. metadata File tags are a type of ____ that describes the contents of a file. This essentially means "data about data." Describe the data contained in a file. file management utility helps you manage files in your operating system logical storage models Storage metaphors help you visualize and mentally organize the files on your disks and other storage devices. File Explorer A utility program bundles with the Windows operating system and designed to help you organize and manipulate the files stored on your computer. File Explorer helps you manipulate files and folders in the following ways: Rename, Copy, Move, Delete. Windows offers a set of preconfigured personal folders, such as My Documents and My Music, for storing your personal data files. library Similar to a folder only in the sense that it can be used to group similar files; however a library doesn't actually store files. Instead, it contains a set of links to files that are stored on various devices for systems and in various folders. file management tips Use descriptive names, Maintain file extensions, Group similar files, Organize your folders from the top down, Consider using default folders, Use Public folders for files you want to share, Do not mix data files and program files, Don't store files in the root directory, Access files from the hard disk, Follow copyright rules, Delete or archive files you no longer need, Be aware of storage locations, *Back up physical storage model Describes what happens on the disks and in the circuits. Storage media must be formatted before it can store files. The formatting process divides the disk into tracks and sectors. disc mastering Process of creating a CD, DVD, or BD by selecting all the files and then copying them in a single session. The process can take some time -- especially when burning a full DVD or BD. packet writing Recording technology that lets you record in multiple sessions. Example: you can copy a few files to a CD during one session, and then at a later date record additional files to the same CD. file system Keep track of the names and locations of files that reside on a storage medium, such as a hard disk. NTFS (New Technology File System). cluster To speed up the process of storing and retrieving data, a disk drive usually work with a group of sectors called a ___ or a block. file shredder software To delete data from a disk in such a way that no one can ever read it, you can use special file shredder software that overwrites supposedly empty sectors with random 1s and 0s. This software is handy if you plan to donate your computer to charitable organization and you want to make sure your personal data no longer remains on the hard disk. Files in the Windows Recycle Bin and similar utilities can be undeleted fragmented files As a computer writes on a disk, parts of files tend to become scattered all over the disk. These ___ ___ are stored in noncontiguous clusters. defragmented utility To regain peak performance, you can use a ___ ___ such as Windows Disk Defragmenter, t rearrange the files on a disk so that they are stored in contiguous clusters. backup Stores the files needed to recover data that's been wiped out by operator error, viruses, or hardware failures. Your backup schedule depends on how much data you can afford to lose. You should test your backup by trying to restore one file. The backup device you select depends on the value of your data, your current equipment, and your budget. A full system backup includes a copy of every file stored on your computer's hard drive. restore Backups allow you to restore data from a backup to the original storage location or to a replacement device. file copies Unique files are difficult to reproduce. Manually copying and pasting requires you to select the files and destination device each time. synchronization Compares the content of files on two devices and makes them the same. Example: a program called Time Machine supplied with Mac OS X is a good example of synchronization software. Windows 8 includes a synchronization utility called File History. boot disk Is a removable storage medium containing the operating system files needed to boot your computer without accessing the hard disk. recovery disk Is a bootable CD, DVD, or other media that contains a complete copy of your computer's hard disk as it existed when the computer was new. recovery partition Is located on the computer's hard disk and contains the necessary files to restore a computer to its original state. Windows Registry An important group of files used by the Windows operating sytsem to store configuration information about all the devices and software installed on a computer system. restore point A snapshot of your computer settings. Restore points are essentially backups of the Windows Registry. If a hard disk problem causes system instability, you might be able to roll back to a restore point when your computer was operational. backup software A set of utility programs designed to back up and restore some or all of the files on a computer's primary storage device. A backup made by copying all the files to a backup device is called a full backup. differential backup makes a backup of only those files that were added or changed since your last full backup session incremental backup makes a backup of the files that were added or changed since the last backupnot necessarily the files that changed from the last full backup bare-mental restore restores the computer in a single step disk image a bit-by-bit copy of the data from all sectors of a disk tablet / smartphone backup Handheld devices are usually backed up by synching themto a desktop or laptop computer. Synching is usually initiated by tethering your handheld device to a full-size computer using a USB cable. iPhones, iPods, and iPads synch with iTunes software, and you have the option to encrypt the backup to prevent your data from exposure if your computer falls victim to an unauthorized intrusion. Many Android devices include backup software, usually accessible from the Settings icon. CHAPTER 5Personal Area Network (PAN) interconnection of personal digital devices or consumer electronics Local Area Network (LAN) connects computers in a limited geographical area Metropolitan Area Network (MAN) public high-speed network with range of about 50 miles Wide Area Network (WAN) covers a large geographical area and typically consists of several smaller networks LAN advantages -LANs enable people to work together-Sharing networked software can reduce costs-Sharing data on a LAN can increase productivity-Sharing networked hardware can reduce costs-Sharing an Internet connection can be cost-effective and convenient-Sharing networked hardware can provide access to a wide range of services and specialized peripheral devices LAN disadvantages -One disadvantage of LANs is that when a network malfunctions, all the resources you're accustomed to accessing are unavailable until the network is repaired-LANs are vulnerable to unauthorized access-LANs are vulnerable to malicious code shared resources hardware, software, and data made available for authorized network users to access node each connection point on a network network interface card (NIC) connect to a LAN, a computer requires network circuitry networked peripheral network-enabled peripheral, is any device that contains network circuitry to directly connect to a network network attached storage (NAS) storage device that directly connects to a network network device or network appliance, is any electronic device that broadcasts network data, boosts signals, or routes data to its destination router central distribution point for getting data to its destination; network devices also include hubs, switches, gateways, bridges, wireless access points, and repeaters communications channel or link, is a physical path or frequency for signal transmissions optical fiber cable composed of many strands of glass tubes that are not much wider than a human hair; data signals speed through these tubes as rays of light; MANs and WANs use these to carry network signals bandwith transmission capacity of a communications channel broadband high-bandwidth communication systems, such as TV and DSL; essential for networks that support many users, and those that carry lots of audio and video data, such as music and movie downloads narrowband less capacity, such as dial-up Internet acccess rules for efficiently transmitting data from one network node to another: -Divide messages into packets-Affix addresses to packets-Initiate transmission-Regulate flow of data-Check for transmission errors-Acknowledge receipt of transmitted data communications protocol refers to a set of rules for efficiently transmitting data from one network note to another handshaking two computers on a network might negotiate their communications protocols packet a "parcel" of data that is sent across a computer network; every packet that travels over a network includes the address of its destination device circuit switching establishes a dedicated, private link between one telephone and another for the duration of a call; this type of switching provides callers with a direct pipeline over which a stream of voice data can flow; inefficent packet switching more efficient than circuit switching; divides a message into several packets that can be routed independently to their destination; messages divided into equal size pickets are easier to handle than an assortment of small, medium, large, and huge files MAC address a unique number assigned to a network interface card when it is manufactured IP address a series of numbers used to identify a network device octet .an IP address such as 204.127.129.1 is separated into 4 sections by periods for the convenience of human readers; each section is called ___ because in binary it is represented by eight bits DHCP (Dynamic Host Configuration Protocol) IP addresses can be obtained through ___; designed to automatically distribute IP addresses; most computers are preconfigured to get an IP address by sending a query to the network device acting as the ___ server. Wired Basic -A wired network uses cables to connect network devices-Wired networks are fast, secure, and simple to configure-Wired connections are more secure than their wireless counterparts-Devices tethered to cables have limited mobility Ethernet -A wired network technology that is defined by IEEE 802.3 standards-Simultaneously broadcasts data packets to all network devices-Vary in speed from 10Mbps to 100Gbps Ethernet adapter also called Ethernet card or NIC; a USB Ethernet adapter plugs into a USB port and can be used with a laptop and desktop computers; Ethernet card installs in an expansion slot inside the system unit of a desktop computer RF signals commonly called radio waves; sent and received by a transceiver which is a combination of a transmitter and a receiver that is equipped with an antenna microwaves provide another option for transporting data wirelessly; they are electromagnetic signals infared light can carry data signals but only for shot distances and with a clear line of sight Wireless Basics -Wireless network technology transports data from one device to another without cables or wires-Slower than wired networks-Security concerns bluetooth a short-range, wireless network technology designed to make its own connections between two devices pairing creates a persistent link between two devices, usually through the exchange of an authentication code called a passkey discovery mode devices equipped with Bluetooth capability can be set into ___ in which they are open for pairing; two devices in discovery mode can "discover" each other and exchange passkeys, one pairing is complete, the two devices can share data without exchanging passkeys again Wi-Fi refers to a set of wireless networking technologies defined by IEEE 802.11 standards wireless ad-hoc protocol devices broadcast directly to each other wireless infrastructure protocol a centralized broadcasting device coordinates communication among network devices Wi-Fi adapter plugs into a USB port or an internal expansion slot dual-band when a router uses both frequencies; offers flexibility to support various network devices and also can over come interference on either of the bands MIMO (multiple-input multiple-output) devices with one or more antennas technology to boost signals and spread them more evenly over the signal range; routers usually have 1-4 antennas and more antennas generally mean more coverage area and good speed even as devices get farther from the router Router Configuration -Plug in the router-Connect the router to a computer-Configure the router-Access the router setup utility-Create a new router password-Enter an SSID for the network-Activate WEP, WPA, or PSK and create an encryption key-Connect an Internet access device-Set up the wireless workstations Router Installation -Look for a Wireless-N router that includes a Gigabit Ethernet switch-Wired and wireless connections-Make sure the number of Ethernet ports is sufficient for the number of wired devices that you intend to connect-Before using your network, you should adjust the router's configuration settings to make sure your network is secure-Stored in router's EEPROM-You must connect a computer to the router-You can use your computer's browser to access the router configuration utility-An SSID (service set identifier) is the name of a wireless network-Use the router configuration software to change the default SSID-Each workstation requires a unique address for sending and receiving data Internet Connection -Your Internet service provider supplies a device called a modem that is designed to carry data to and from the Internet-This device typically has a standard Ethernet port that can be connected to a router-Most routers supply a WAN port designed for an Internet connection-Plug a standard network cable into the router's WAN port and connect the other end of the cable into the Internet modem Device Connection -Simply turn on any Windows computer with wireless capability and make sure that it is in range of your router-Macs automatically sense available networks and give you the option of connecting to them-Any device that has Wi-Fi capability should be able to connect to your network SSID (service set identifier) name of a wireless network wireless encryption scrambles the data transmitted between wireless devices and then unscrambles the data only on devices that have a valid encryption key WEP (Wired Equivalent Privacy) original wireless encryption protocol WPA (Wi-Fi Protected Access) WPA2; offers stronger protection by making sure that packets have not been intercepted or tampered with in any way PSK (pre-shared key) personal mode; type of WPA used on most home networks wireless encryption key network security key; basis for scrambling and unscrambling the data transmitted between wireless devices; all workstations use the same key to scramble and unscramble data file sharing -allows files containing documents, photos, music, and other data to be accessed from computers other than the one on which they are stored-Once your network gives you access to other computers on the network, you can view a list of files stored there-when you activate file sharing, files in Public folders can be accessed by other network users-You also can make specific files shareable Network Discovery a setting that affects whether your computer can see other computers on a network, and whether your computer can be seen by others public folder designed to hold files and folders that you want to share with other people on your network homegroup collection of trusted Windows computers that automatically share files and folders; access can be protected by a password file server a computer whose primary purpose is to be repository for files that can be accessed by network workstations; example: an old desktop computer to store lots of big video files Network Troubleshoothing Network problems can stem from a variety of sources:-Cables-Security-Interference-Settings-Switches-Signal strength-Network devices Wi-Fi Security -Networks with wired or wireless connections are vulnerable to a variety of threats-Wireless signals are broadcast through the air; and like the signals from a radio station, they can be picked up by any device equipped with a receiver tuned to the right frequency-Your network router maintains a list of clients that are accessing your network using wired or wireless connections encryption transforms a message so that its contents are hidden from unauthorized readers; converting plaintext into ciphertext plaintext cleartext; has not yet been encrypted ciphertext an encrypted message decryption the opposite of encryption cryptogrpahic algorithm procedure for encrypting or decrypting a message cryptogrpahic key or simply key; a word, number, or phrase that must be known to encrypt a decrypt a message weak encryption easy to decrypt even without the algorithm and key; unauthorized decryptio is sometimes referred to as breaking or cracking a code strong encryption "very difficult to break" AES (Advanced Encryption Standard) technology used for WPA2; one of the strongest cryptographic algorithms; encryption methods can be broken by the use of expensive, specialized, code-breaking computers symmetric key encryption key used to encrypt s message is also used to decrypt the message; used to encrypt stationary data such as corporate financial records and data that travels over WLANs public key encryption (PKE) eliminates key distribution problem, by using one key to encrypt a message and another key to decrypt the message; when personal computer users want to encrypt email or other documents, they turn to public key encryption software such as PGP (Pretty Good Privacy), GnuPG, or AxCrypt CHAPTER 6Always-on connection In the context of Internet access, a permanent connection, as opposed to a connection that is established and dropped as needed Anonymous FTP A type of FTP access that requires no account on a server, but rather can be accessed using "anonymous" as the user ID Asymmetric Internet connection Any connection to the Internet in which the upstream speed differs from the downstream speed Asynchronous communications A communications mode, such as forums, e-mail, blogs, and tweets, in which participating parties do not have to be online at the same time BitTorrent A peer-to-peer technology in which pieces of files are distributed to and from a collection of networked computers; used for distributing music and movies over the Internet Blog (WeB LOG) A publicly-accessible personal journal posted on the Web. Blogs often reflect the personality of the author and are typically updated daily Cable Internet service A type of Internet connection offered to subscribers by cable television companies Cable modem A communications device that can be used to connect a computer to the Internet via the cable TV infrastructure Chat Interactive real-time person-to-person communication over a network Communications port In the context of computer networking, a virtual location for data that arrives or leaves the device; common ports include 21 for FTP, 110 for e-mail, and 80 for Web data Dial-up connection A connection that uses a phone line to establish a temporary Internet connection DNS cache poisoning An exploit in which the DNS database is changed in such as way that a URL no longer connects to the correct Web site DOCSIS (Data Over Cable Service Interface Specification) A security technology used for filtering packets and maintaining customer privacy on cable Internet services Domain name Short for "fully qualified domain name"; an identifying name by which host computers on the Internet are familiarly known (for example, "coca-cola.com"). Domain name server A computer that hosts the domain name system database Domain Name System (DNS) A large database of unique IP addresses that correspond with domain names Downstream speed The rate at which transmitted data flows from a host or server to a local computer (contrast with upstream speed) DSL (Digital Subscriber Line) A high-speed Internet connection that uses existing telephone lines, requiring close proximity to a switching station DSL filter Devices that are commonly used to prevent interference from analog devices, such as telephones, that use the same line as DSL devices DSL modem A device that sends and receives digital data to and from computers over telephone lines Dynamic IP address A temporarily assigned IP address usually provided by an ISP Firewall Software or hardware designed to analyze and control incoming and outgoing packets on a network, used to enhance security by filtering out potential intrusion attempts Fixed Internet access Any Internet access service designed to be used from a fixed, non-portable location, i. e., dial-up, ISDN, DSL, and cable Internet service Fixed wireless Internet service High-speed, wide area Internet service alternative to cable and DSL that transmits data wirelessly using RF signals FTP (File Transfer Protocol) A set of rules for uploading and downloading files between a client computer and a remote server FTP client The computer or software that is used to access an FTP server and transfer files to it or from it FTP server A computer that stores and distributes files to remote client computers Grid computing system A network of computers harnessed together to perform processing tasks; distributed grids like the SETI project use ad hoc and diverse Internet connected computers; also see cloud computing ICANN (Internet Corporation for Assigned Names and Numbers) A global organization that coordinates the management of the Internet's domain name system, IP addresses, and protocol parameters Instant messaging A private chat in which users can communicate with each other in real time using electronically transmitted text messages Internet backbone The major communications links that form the core of the Internet Internet forum An asynchronous online discussion in which participants post comments to discussion threads, which can be read at a later time by other participants Internet service provider (ISP) A company that provides Internet access to businesses, organizations, and individuals Intrusion In the context of computer security, the unauthorized access to a computer system IP (Internet Protocol) One of the main protocols of TCP/IP; responsible for addressing packets so that they can be routed to their destinations; IPv4 offers 32-bit addresses whereas IPv6 offers 128-bit addresses. Jitter Deviations in the timing of a digital signal that can interfere with communications, especially voice over IP Latency The elapsed time it takes for a packet of data to arrive at its destination MiFi A small, wireless router that connects to a cellular data network, creating a mobile WiFi hotspot Mobile broadband High-bandwidth wireless technology that was developed for sending digital data over cell phone systems Mobile Internet access Any service that allows subscribers to access the Internet while on the go Modem A device that modulates and demodulates a signal, typically used to send data from a computer to the Internet over telephone, cable television, or satellite networks Network access points (NAP) Internet nodes that link together different network service providers so that data can be transferred from one service provider to the other Network address translation (NAT) A security technique that allows a LAN to use one type of IP address for intra-network data and another type of address for data traveling to and from the Internet Network service providers (NSP) Companies that maintain a series of nationwide Internet links P2P file sharing A practice in which individuals can obtain music, video, and other types of files from other users on a network; sometimes the files are shared without authorization from the copyright holder Packet loss The situation in which data bits are lost in transit, requiring them to be resent which significantly increases the time required for an intact message to arrive at its destination Ping (Packet INternet Groper) A command on a TCP/IP network that sends a test packet to a specified IP address and waits for a reply Port probe An exploit used by hackers to locate computer ports that can be used for surreptitious access; also called a port scan Portable Internet access Any type of Internet service, such as portable satellite, that can be moved from one place to another Private IP address An IP address that cannot be routed over the Internet Protocol suite A group of protocols, such as TCP and IP, that work together Real-time messaging system Technologies, such as instant messaging and chat, that allow people to exchange messages when they are online Routable IP address A network address that can be routed over the Internet; contrast to private IP address Satellite Internet service A high-speed Internet service that uses a geosynchronous or low-earth orbit satellite to send data directly to satellite dishes owned by individuals Satellite modem A device that connects a computer to a satellite for purposes of accessing the Internet Software as a service A cloud computing model in which consumers access applications using a browser, usually fee based Static IP address A permanently assigned and unique IP address, used by hosts or servers Symmetric Internet connection Any connection to the Internet in which the upstream speed is the same as the downstream speed Synchronous communications A communications mode, such as VoIP, in which participants must be online at the same time TCP (Transmission Control Protocol) The protocol within TCP/IP that is responsible for establishing a data connection between two hosts and breaking data into packets TCP/IP (Transmission Control Protocol/Internet Protocol) The primary protocol suite for transmitting messages over the Internet Top-level domain A major domain category into which groups of computers on the Internet are divided, such as com, edu, gov, int, mil, net, and org Traceroute A network utility that records a packet's path, the number of hops, and the time it takes for the packet to make each hop Tweet A short message, sometimes called a microblog, posted on Twitter Upstream speed The rate at which data is transmitted from your home computer to the Internet Virtual private network (VPN) A network connection that typically carries encrypted data over the Internet to and from a remote access server Voiceband modem The type of modem typically used to connect a computer to a telephone line VoIP (Voice over Internet Protocol) Hardware, software, and protocols used to make telephone-style calls over the Internet. Also referred to as Internet telephony. WAP (Wireless Access Protocol) A communications protocol that provides Internet access for handheld devices Wi-Fi hotspot The geographical area in which you can connect to a Wi-Fi signal, such as a Wi-Fi equipped campus or coffeehouse Wiki Software that allows users to collaborate to create, change, and link Web pages. Used for applications such as Wikipedia and open source project management WiMAX Fixed wireless Internet service based on Ethernet protocols with a range of 30 miles and a transmission speed of 70 Mbps CHAPTER 7Web (short for World Wide Web) is a collection of document, image, video, and sound files, that can be linked and accessed over the Internet using a protocol called HTTP hypertext describes a computer that could store literary documents, link them according to logical relationships, and allow researchers to comment and annotate what they read Web site contains a collection of related information organized and formatted so it can be accessed using software called a browser Web server Internet-based computer that accepts requests from browsers. Servers collect the requested information and transmit it back in a format that the browser can display in the form of a Web-page Web page product or output of one or more Web-based files displayed in a format similar to a page in a book. Web-pages can dynamically incorporate videos, sounds, and interactive elements Web browser -or just browser is client software that displays Web page elements and handles links between pages; -examples: Internet Explorer, Mozilla Firefox, Google Chrome, Safari-It is a good idea to upgrade when a new version of your browser becomes available-If your browser does not have built-in support for a file format required to display or play a Web page element, you can download the necessary software-A plug-in is a program that extends a browser's ability to work with file formats hypertext link when using a browser, you can access a Web page by clicking a ___ or simply referred to as a link or by typing a URL URL (Uniform Resource Locator) a Web pages unique address examples: https://www.youtube.com/ which is the URL for YouTube Web 2.0 wikis, blogs, social networking Web 3.0 cloud computing and other new technologies HTML (Hypertext Markup Language) is a set of specifications for creating documents that a browser can display as a Web page markup language HTML is called ___ because authors mark up documents by inserting special instructions called HTML tags HTML tags specify how the document should appear when displayed on a computer screen or printed HTML 5 current version of HTML XHTML markup language very similar to HTML, but can be customized with tags that describe the data in databases; more rigidly structured and a bit more complex than HTML and must adhere to a strict set of syntax rules HTML docuement HTML tags are incorporated into an ___, which is similar to a word processing file but has an .htm or .html extension; tags such as and , are enclosed in angle brackets and embedded in the document which the Web page attempts to follow instead of showing the tags or brackets; example: an image will appear source docuement HTML document is sometimes referred to as ___ because it is the source of the HTML tags used to construct a Web page HTTP protocol that works with TCP/IP to get Web resources to your desktop socket abstract concept that represents one end of a connection persistent HTTP connection reuses the same HTTP connection to send and receive multiple requests; today's browsers use this to obtain text, images, and audio for a Web page during a single session HTTP status code indicates whether the browser's request could be fulfilled Web cache or browser history; when your browser fetches pages and graphics to form a Web page, it stores that material on your computer in temporary files plug-in program that extends a browser's ability to work with file formats cookie small chunk of data generated by a Web server and stored in a text file on computer's hard disk; fix problems caused by HTTP's stateless protocol HTTP stateless protocol maintains no record of the pages you visit at a Web site HTML conversation utility adds HTML tags to a document, spread-sheet, or other text based file to create an HTML document that can be displayed by a browser Web authoring software or HTML editors; which provide tools specifically designed to enter and format Web page text, graphics, and links HTML form uses the tag to accept typed input Pages Interactive and dynamic Web sites are possible when programming and scripting technologies supplement native HTML features client-side when the HTML source document that's received by your local browser handles interactions server-side when interactions are handled by a remote server JavaScript commonly used to add logic and other programmable elements to a Web page Web search engine or search engine; is a program designed to help people locate information on the Web by formulating simple queries consisting of one or more words called keywords or search terms Web crawler Web spider; automated methodically visit Web sites meta keyword entered into a header section of a Web page when it is created and is supposed to describe the page contents Keyword stuffing unethical practice in which meta keywords are manipulated to gain high relevancy rankings search engine indexer software that pulls keywords from a Web page and stores them in an index database query processor looks for your search terms in search engine's indexed database and returns a list of relevant Web sites Link popularity measured by quality and quantity of links from one Web page to others sponsored links some search engines accept paid ads called ___, which are bumped to the top positions on the results list search operator word or symbol that describes a relationship between search terms and thereby helps you create a more focused query, examples: and, or, not, " ", *, .. (two dots) e-commerce -typically refers to business transactions that are conducted electronically over a computer network-e-commerce offers some unique advantages over brick-and-mortar stores and mail-order catalogs-easily search for merchandise-easily compare prices and products e-commerce business models -B2C: business to consumer (Amazon)-C2C: consumer to consumer (eBay)-B2B: business to business-B2G: business to government C2C -At C2C auction and online classified advertising e-commerce sites, consumers offer goods and services to other consumers-C2C sites are hosted by an e-commerce provider such as eBay or craigslist-Many C2C sites uses e-mail forwarding to protect participants' privacy banner ad advertisement embedded at the top of a Web page hover ad overlays the content on a Web page, sometimes obscuring it until you click the ad or its timer expires and the ad disapears pop-up ad advertisement that appears in a separate window when you connect to a Web page. click-through rate number of times that site visitors click the ad to connect to the advertiser's site ad-blocking software prevent ads from appearing on their screens online shopping cart cyberspace version of the metal cart you wheel around a store secure connections -encrypts the data transmitted between your computer and a Web site-SSL (Secure Sockets Layer)-TLS (Transport Layer Security)-HTTPS (Hypertext Transfer Protocol Secure) online payment -The most popular ways to make online payments include submitting your credit card number directly to a merchant and using a third-party payment service such as PayPal-Online shoppers are justifiably worried that personal information and credit card numbers supplied in the course of an e-commerce transaction might be hijacked and used inappropriately P2P payment -Person-to-person payments are an alternative to credit cards-The payment service is the only entity that sees your credit card number HTTPS (Hypertext Transfer Protocol Secure); combination of HTTP and SSL/TSL that provides a secure connection for Web-based transactions email message electronic document transmitted over a computer network email system email services email server computer than essentially acts as a central post office for a group of people email account electronic mailbox message header divided into fields that contain the sender's e-mail address, the recipient's address, a subject line, and the date and time the message was written email client software software used to send, receive, and manage messages local email email systems based on a local client software email address example: imsoamazing@yahoo.com store and forward messages downloaded to a folder on a local storage device POP3 or IMAP (Post Office Protocol ver 3) or (Internet Message Access Protocol) are used to manage your incoming mail; POP3 deletes messages from the server after they are downloaded; IMAP leaves them until specifically deleted SMTP handles outgoing mail Webmail typically a free service accessed using a browser email attachments -files that travel with an e-mail message-Don't send huge attachments-Explain all attachments-Don't open suspicious attachments-You can save attachments-You might have to download a plug-in or player MIME email software converts e-mail attachments using a conversion Netiquette online jargon for Internet etiquette; it is a series of customs or guidelines for maintaining civilized and effective communications in online discussions and email exchanges ad serving cookies claim that the data in their cookies is used simply to select and display ads that might interest you first party cookie created by the Web site your are visiting third party cookie set by an affiliated site private browsing provides additional ways to surf the Web without accumulating a trail of cookies Flash cookie also called a local shared object, is the Flash equivalent of a conventional Web cookie anonymous proxy service uses an intermediary, proxy, server to relay Web page request after masking the originating IP address Web bug or clear GIF is typically a 1x1 pixel graphic embedded in a Web page or e-mail message. It is almost invisible due to its size and is designed to track who's reading the Web page or e-mail message antispyware type of security software designed to identify and neutralize Web bugs, ad-serving cookies, and other spyware spam -unwanted electronic junk mail about medical products, low-cost loans, and fake software upgrades that arrive in your online mailbox-spam has turned into another major hacking tool for cybercriminals spam filter type of utility software that captures unsolicited e-mail messages before they reach your inbox Phishing -e-mail based scam designed to persuade you to reveal confidential information, such as your bank account number or Social Security number-If you don't want to become a phishing victim, be suspicious of e-mail messages that supposedly come from banks, ISPs, online payment services, operating system publishers, and online merchants fake sites fake, or fraudulent, Web site looks legitimate, but has been created by a third party to be a very clever replica of a legitimate Web site pharming -an exploit that redirects users to fake sites by poisoning a domain name server with a false IP address-Pharming is more surreptitious and tougher to detect than most other hacker schemes