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CGS1100 5/25/2017 1 An electronic device used to process data. The most common computer today? ◦ the Personal Computer. 5/25/2017 CGS1100 2 2% 3% PCs In-Use (#M) 2005 2% 2% 1. U.S. 3% 3% 4% 2. Japan 34% 4% 3. China 4. Germany 4% 5. UK 5% 6. France 6% 7. South Korea 11% 8% 8. Italy 9% 9. Canada 3 5/25/2017 CG S1 10 0 CGS1100 5/25/2017 4 ◦ Hardware the physical part of the computer ◦ Software the programs that run the hardware ◦ Data raw facts that are turned into useful information ◦ People the individuals that use computers (the user) the software and hardware designers CGS1100 5/25/2017 5 ◦ The Central Processing Unit (CPU) Intel Pentium ◦ Memory ROM and RAM Measured in bytes, kilobytes, megabytes, gigabytes, etc. ◦ Input and Output devices Moves data in and moves processed information out ◦ Storage devices Floppy disk drive, hard disk drive, CDROM, CDR, CDRW, DVD drives, Zip drives CGS1100 5/25/2017 6 The Central Processing Unit ◦ Turns data into useful information ◦ Is connected to the motherboard ◦ Is the brain of the computer ◦ Not the same thing as “the box” 5/25/2017 CGS1100 7 Read Only Memory (ROM) ◦ Contains the information needed to boot the system ◦ Nonvolatile (data cannot be changed) Random Access Memory (RAM) ◦ Working memory ◦ Volatile (is lost when machine is turned off) ◦ The more RAM, the faster the computer will run and the more it can do ◦ The more software you can upgrade before having to upgrade hardware 5/25/2017 CGS1100 8 Accept data and instructions from the user ◦ ◦ ◦ ◦ ◦ ◦ ◦ Keyboards Mice and Trackballs Touch-Screen Monitors Scanners Microphones Digital Cameras IPods CGS1100 5/25/2017 9 Return processed information back to the user. ◦ Floppy Disk drive ◦ Printer ◦ Monitor ◦ Hard drive ◦ CD’s/DVD’s ◦ Speakers, IPods ◦ Key Drives (USB port hard drives) CGS1100 5/25/2017 10 Holds data Large storage capacity ◦ measured in Megabytes (Mb) one million bytes Gigabytes (Gb) one billion bytes Terabytes (Tb) one trillion bytes Nonvolatile CGS1100 5/25/2017 11 Hard drives Floppy Disk drives Tape drives Optical drives ◦ Compact Disks CD-ROM, CD-R & CD-RW ◦ Digital Versatile Disks DVD, DVD-R & DVD-RW CGS1100 5/25/2017 12 New Drives on the Horizon? ◦ Plasma drives ◦ Holographic imaging drives ◦ Portable hard drives Thumb drives Memory sticks CGS1100 5/25/2017 13 A set of instructions When executed tells the computer and its peripheral devices ◦ what actions to perform and ◦ in what order to perform them CGS1100 5/25/2017 14 System Software ◦ Operating systems, such as Windows (Vista, XP & 2000), DOS, Linux, iMac, AS400 Application Software & Suites ◦ Word processing, Spreadsheets, Databases, Multimedia, Presentation & Graphics, Entertainment, Education, Utilities, Communications CGS1100 5/25/2017 15 Supercomputers Mainframes Minicomputers The Cray IBM 360, AS400 System 36/38 CGS1100 5/25/2017 16 Microcomputers (PCs) ◦ Workstation ◦ Desktop ◦ Laptop or Portable ◦ Personal Digital Assistant (PDAs) ◦ eBook ◦ Tablet ◦ Blackberry CGS1100 5/25/2017 17 CGS1100 5/25/2017 18 Binary Numbering System ◦ Uses 2 digits: 0 and 1 ◦ All data is stored within the computer as 0’s and 1’s. Decimal Numbering System ◦ Uses 10 digits: 0, 1, 2, 3, 4, 5, 6, 7, 8 & 9 Other Numbering Systems CGS1100 5/25/2017 19 A Bit ◦ The smallest possible unit of data. ◦ In binary, either a 0 or a 1. A Byte ◦ ◦ ◦ ◦ A combination of 8 bits. Used to represent up to 256 different values. Used to represent characters. Ex. 0100 0001 = A CGS1100 5/25/2017 20 ASCII ◦ An 8-bit coding system used on personal computers. Unicode ◦ A 16-bit coding system used to represent characters from almost every language in the world. CGS1100 5/25/2017 21 Don’t skimp on memory Purchase as much disk space as possible Review online reviews of hardware & software Don’t forget the bundled software Don’t forget your surroundings Insist on a 30-day unconditional return policy for full refund Insist on a price guarantee; i.e., if the price goes down within 30 days, you are entitled to the rebate Pay with a credit card ◦ Increases leverage to enforce above items ◦ May double the manufacturer’s warranty up to an additional year CGS1100 5/25/2017 22 CGS1100 5/25/2017 23 Connect computers ◦ Uses telephone lines from one location to another. Measured in transfer rates of bits per second CGS1100 5/25/2017 24 Example of an Analog Signal Sound No Sound Example of a Digital Signal CGS1100 5/25/2017 25 Tin can Modem Modem Analog Signal CGS1100 5/25/2017 26 Connect computers together so that they can communicate, exchange information, and pool resources. Are connected by nodes Categories ◦ ◦ ◦ ◦ Local Area Network (LAN) Metropolitan Area Network (MAN) Wide Area Network (WAN) Internet CGS1100 5/25/2017 27 File server networks 1. ◦ ◦ ◦ 5/25/2017 A central computer with a large hard disk serves as a common place to store and access files. Processing is restricted to the file server. Restricts access by nodes to file server. CGS1100 28 Client/Server networks 2. ◦ ◦ ◦ 5/25/2017 Shares both files and programs with the nodes. Processing is shared between the server and the nodes. What you’re on in here! CGS1100 29 Peer-to-peer networks 2. ◦ ◦ 5/25/2017 All nodes share resources equally. All nodes can act as file servers and can access common peripherals. CGS1100 30 CGS1100 5/25/2017 31 A file is a set of instructions or data ◦ Program file: Microsoft Word or Microsoft Excel ◦ Data File: Document or workbook CGS1100 5/25/2017 32 Copy, move, rename or delete a file Folder ◦ allows us to organize our files ◦ May contain files and/or other folders Back up strategy -- is critical ◦ What (data), When (whenever it changes), Where (off site), How (Windows Explorer), and Who (you) ◦ Back up your work! CGS1100 5/25/2017 33 CGS1100 5/25/2017 34 The complement to ARPANET. Became higher-capacity network The backbone of the Internet Could handle the increased user load Developed into a much larger network sharing information among government, business and commercial enterprises. CGS1100 5/25/2017 35 Individual PCs are connected to a local area network. Then connected via a router to the Internet using a TCP/IP connection Then connected to other LANs. 5/25/2017 Router TCP/IP Internet CGS1100 36 TCP/IP ◦ Transmission Control Protocol/Internet Protocol ◦ The universal language of the Internet ◦ Includes the specifications that identify individual computers and the exchange of data between computers. CGS1100 5/25/2017 37 IP (Internet Protocol) the 4-part numeric address that identifies each computer. ◦ 10.2.2.166 DNS (Domain Name System) the name counterpart to the IP address. ◦ [email protected] ◦ Easier to use than remembering number CGS1100 5/25/2017 38 DOMAIN TYPE OF ORGANIZATION .com Business (commercial) .edu Educational .gov Government .mil Military .net Gateway or Host .org Any other type of organization Examples: 5/25/2017 owc.edu uwf.edu CGS1100 yahoo.com 39 An exchange of electronic information Can also include data files and program files to email messages No expectation of privacy 5/25/2017 Every e-mail address is unique You can obtain an account ◦ Through your school, ◦ pay for an account through an ISP such as AOL, or ◦ get free email accounts at sites like www.hotmail.com or www.yahoo.com or www.gmail.com CGS1100 40 Consists of two parts ◦ A username and a host computer [email protected] Highest-level domain Host computer Username A good Internet E-mail Address must contain the @ symbol CGS1100 5/25/2017 41 • E-commerce is the exchange of goods and services via the Internet. – It requires a buyer and seller, and a ‘place to meet’ Advantages for the Seller ◦ Open 24/7 ◦ Shoppers from anywhere ◦ Virtual inventory is cheaper and extensive ◦ Lower transaction costs ◦ Target your customers Advantages for the Buyer ◦ Open 24/7 ◦ Never leave home ◦ Easy to view and explore product line ◦ Comparison shop ◦ Web site knows you CGS1100 5/25/2017 42 News & News Groups ◦ A form of public bulletin board ◦ Each news group is dedicated to one particular subject ◦ Can quickly become an annoyance! CGS1100 5/25/2017 43 FTP (File Transfer Protocol) ◦ A tool used to copy files from one computer to another. ◦ Allows you to upload content to a website CGS1100 5/25/2017 44 Internet Relay Chat (IRC) ◦ Chat rooms ◦ a means of communicating with others in real time ◦ Play Safe! Don’t give out your name or anything personal! CGS1100 5/25/2017 45 The World Wide Web Created in the late 1980’s at the European Particle Physics Laboratory in Geneva, Switzerland A method for incorporating footnotes, figures, and cross-references into online hypertext documents ◦ Uses HTTP (Hypertext Transfer Protocol) and HTML (Hypertext Markup Language) HTTPS (Hypertext Transfer Protocol Secure) CGS1100 5/25/2017 46 ◦ HTTP (Hypertext Transfer Protocol) a set of rules that provide the internal structure to the WWW ◦ HTML (Hypertext Markup Language). A page-description language that translates document formatting to formatting for the Web ◦ HTTPS Secure protocol for confidential transactions ◦ URL (Uniform Resource Locator) Internet address in a special format that can be read by HTTP. Ex. http://www.yahoo.com CGS1100 5/25/2017 47 Web browsers make negotiating the Web easier. ◦ Most well-known browsers Internet Explorer Firefox (Mosaic/Mozilla) Safari Netscape Navigator With IE and Firefox making 81.28% 12.96% 3.93% (< 1%) up over 90% of the market Percentages from PC Magazine, January 2007 CGS1100 5/25/2017 48 •High-Speed Data Links - Cost More! Cox Cable ◦ connection made through TV cable ◦ up to ten times as fast as regular telephone lines ◦ A family of digital telecommunications protocols designed to allow high speed data communication over the existing copper telephone lines between end-users and telephone companies. ISDN (Integrated Services Digital Network) ◦ combines voice, data, and control signaling through a single dedicated circuit ◦ can transfer data at rates up 128,000 bits per second. DSL (Digital Subscriber Line) Hughes.net (Direcway) ◦ Connection made through Satellite CGS1100 5/25/2017 49 Protection ◦ Firewalls ◦ Netiquette used to control access to individual networks Guidelines Netiquette by Virginia Shea ◦ Passwords used to restrict access to files, programs or networks A1234z is better than Spouse’s name Pet’s name Last 4 SS numbers Anniversary or Birthday dates Courtesy Ethics ◦ FBI Internet Fraudulent ◦ Urban Legends ◦ Hoaxbusters CGS1100 5/25/2017 50 Password Length 36 (no case, letters & digits) 0 minutes 52 (case sensitive) 96 (all printable characters) 4 26 (no upper case/ letters only 0 minutes 1 minute 12 minutes 5 0 minutes 10 minutes 1 hour 22 hours 6 50 minutes 6 hours 2.2 days 3 months 7 22 hours 9 days 4 months 23 years 8 24 days 10.5 months 17 years 2,287 years 9 21 months 32.6 years 881 years 219,000 years 10 45 years 1,159 years 45,858 years 21 million years CGS1100 5/25/2017 51 Forwarding Chain letters If you love me… Scams ◦ No kidding! I really know this person! ◦ Kidney Transplant CGS1100 5/25/2017 52 CGS1100 5/25/2017 53