What You'll Be Learning About Week 1

• Overview of computer software
• Introduction to MS Windows - File Manager, NotePad Editor
• Definition of the Internet
• History of the Internet
• Demographics - Who, What, Where
• Host Names and Addresses
• The World Wide Web (WWW)
• Using the Netscape WWW Browser
• WWW Search Engines
• More Netscape Features

Systems Software

manages the resources of a computer system and makes its operations more efficient and effective.

• Operating System
  • all computers require an OS
  • coordinates computer hardware, and supervises storage, input, output and processing.
  • acts as an interface between the user, hardware and the application software.
  • its function is to provide a basic set of computer instructions.
  • Some of the popular OSs are:

    DOS, MS-DOS

    Developed for use on microcomputers. Supports one user at a time.

    Unix

    Developed at Bell Labs in 1969. It is designed to handle multiusers and multitasking. It is portable, i. e. can be moved from one machine to another.

    OS/2

    Developed by IBM and Microsoft. It is a multitasking system. Requires a larger memory as compared to MS-DOS.

• Language Translators - A translator converts a statement from a high level programming language (source code) into machine language (object code).

  - programming languages are necessary because computers work with binary data. It is difficult, and error prone to write programs in binary.

  Translators are of two types:

  • interpreter

    translates one instruction at a time

    useful when small programs to be run only once or few times

  • compiler

    translates complete program at a time

    it is a two stage process

    useful for larger programs that are to be run number of times

• Utility programs Programs used to merge and sort files, keep track of computer jobs being run, keep track of number of users and resource utilization etc.

Application Software

• Word Processing Software (a document presentation tool) - to create, print and edit documents
• Spreadsheet Software (a number productivity tool) - to add, subtract, and perform calculations on data stored in rows and columns
• Database Software (a data management tool) - to enter, retrieve, and update data very efficiently by storing data in an organized manner
• Graphics Software (a data presentation tool) - to convert numbers and text in a graphics form
• Communication Software ( a connectivity tool) - to establish a communication link between computers

Programming Languages

- enable people to write software to develop applications.

- enable people to solve a problem that cannot be handled by the off-the-shelf application software.

- Ex: COBOL, BASIC, FORTRAN, PASCAL, C, C++, Assembly language, ..

- Generations of languages

1st generation: Machine language

2nd generation: Assembly language

3rd generation: procedural languages (high-level)

4th generation: non-procedural languages (very high-level)

Telecommunications

• What is communications? - Transmission of data and information over a communications channel, such as a standard telephone line, between one computer and the other computer.
• Communication Channel - is the path the data follows as it is transmitted from the sender to the receiver.

  Ex: Twisted pair, coaxial cable, fiber optics, microwave transmission, satellite transmission, and wireless transmission.

• Communication Equipment: Modem ( Modulator-Demodulator ) - can transmit data at rates from 300 to 38,400 bits per second (bps)

  - it converts digital signal it analog signal at the sending end and converts analog signal to digital signal at the receiving end.

• Communication Networks
  • LAN

    - usually privately owned

    - covers a limited geographic area

    - frequently used software can be shared - file-server environment, client-server environment

    - Hardware Resource sharing - sharing a printer

  • WAN

    - geographic in scope

    - public WAN companies include common carriers such as telephone companies.

Introduction to MS Windows -File Manager and NotePad Editor

Windows 3.1

• STARTING WINDOWS. After Windows is set up on your computer, to start Windows you simply at the command prompt (for example, C>), type win and then press enter. (You may start Windows differently if you use a system menu such as those computers in Engelhard Lab).
• THE BASICS. As you work with Windows, there are a few basic terms you need to become familiar with. You do your work in a rectangular areas of the screen called windows. These windows appear on the background called desktp. The applications you work with (such as your word-processing or spreadsheet applications) are represented in Windows by small graphical symbols called icons. You often carry out an action in Windows by choosing an item: For example, choosing an icon can start an application. You choose an icon by double-clicking it with the mouse.
• PROGRAM MANAGER. When you start Windows, the first thing you see is Program Manager, which continues to run as long as you are using Windows. Initially, the Program Manager window displays the contents of the Main group. A group is a collection of applications you can run. The names and icons for the applications in the group are displayed in the group window.
  Program Manager also displays icons for other groups of applications:Accessories, Games, Startup, and others.
  You can perform many important tasks by using Program Manager. For example you can start applications, organize your applications into groups for easy access, create and delete groups, add applications to group and delete applications from a group, add applications to the StartUp group so that they start when Windos starts, and quit Windows.
• STARTING AN APPLICATION. From Program Manager, you can easily start an application by using the mouse to double-click (or choose) its icons, called a programitem icon. Yo may need to open another group window to find the icon representing the application you want to use. For example, you need to open the Accessories group to start Notepad. Once opened, the Accessories group window displays icons for additional applications you can run. When you double-click the icon, in this case Notepad, the application appears in an application window, ready for you to use.
  The Notepad window is now the active window. The active window is generally the window in the foreground. To make another window active, you click anywhere in the window you desire.
• USING MENU. Each application window, and other windows as well, has menu names located at a menu bar (beneath the title bar). A menu contains a list of commands, which are actions you can carry out in Windows. To choose a menu name or command, you click it once.
• REDUCING AN APPLICATION WINDOW TO AN ICON. As you work with Windows, you may want to temporarily puy aside an application but keep it running and easily available to use later. You can avoid clutter on your screen if you reduce the application window to an icon by clicking its Minimize buttons; the icon stays on the Windows desktop until you need to use the application again. An icon has the application runs, but an application icon takes up less space.
• QUITTING AN APPLICATION. When you finish using an application, you may want to quit it to free memory for other tasks. Uisng a mouse, you can quit an application as easily as starting it. The quickest way to quit is to double-click the application's Control-menu box. While quitting, if you have any usaved work, Windows prompts you to save it before the application window closes.
• FILE MANAGER. File Manager provides a graphical representation of files and directories to help you organize them and simplify file maintenance. You can start File Manager by double-clicking its icon in the Main group window. You can perform many tasks by using File Manager.
  
  • Files and Directories.
    A file is an electronic document or an application or program that has been named and its stored on your computer. A file could be a document you have written or the application you used to create the document. Files have unique names, such as LETTER.TXT, and they can be organized into directories.
    A directory is a collection of files and other directories (subdirectories). Two directories that are likely to be on your computer are WINDOWS and SYSTEM. The WINDOWS directory contains the SYSTEM subdirectory, in addition to many of the Windows files. The SYSTEM directory contains additional files.
    A directory window appears in the main File Manager window. It graphically displays the relationship of the directories and files stored on a disk drive.
    The left side of the window displays the directory tree, and the right side displays the contents of the current directory.
  • Viewing Directory Contents.
    By using File Manager, you can easily scan the contents of a directory by clicking (selecting) its name or icon on the left side of the window.
  • Scrolling to View Information.
    When a file has more text or graphics than can fit inside a window, you can use scroll bars to bring the rest of the information into view.
  • Moving and Copying Files.
    With the drag and drop feature available in File Manager, you can use your mouse to move or copy files quickly.
    For example, to copy a file from you hard disk to a disk in drive A, first position the mouse pointer on the file icon. Then press and hold down the left mouse button and move (drag) the file icon to the drive icon labeled "a". Finally, relase the mouse button, dropping the file icon onto the drive icon.
    You can move a file to a different drive by pressing and holding down the SHIFT or ALT key while you drag the file icon to drive icon. You can also move and copy files from one directory to another by dragging file icons.
• SWITCHING BETWEEN APPLICATIONS. Using Windows to run more than one application at a time can make your job much easier. Bit when several windows are open, it may become dificult to find applications beneath overlappping windows. An easy way to keep track of your application is to use the Windows fast application-switching feature. You can switch quickly to another application by pressing and holding ALT key and then pressing the TAB key repeatedly. As you continue to press TAB, the title of each application currentlyu running in Windows appears in the center of your screen. When you see the application you want to use, release ALT+TAB. The application window appears in the foreground.
• QUITTING WINDOWS. Before turning off your computer, it is recommended that you quit Windows. You can quit Windows by double-clicking the Control-menu box in Program Manager.

NOTEPAD

• STARTING A NOTEPAD APPLICATION. To start a NotePad application, you need to have the Accessories window open. Once the Accessories window is open, double-click on the NotePad Application icon.
• WRITTING YOUR DOCUMENT. Once you have the NotePad application run, you may start creating your document by typing what texts, words and sentences you want to have in your document.
• SAVING YOUR WORK. To save your work for the first time, you can use the menu bar beneath the NotePad window-title. You need to select the "FILE" menu and drag down to the "SAVE AS" command. The application will give you a dialog box and ask you to supply an 8-character long filename for your document. Pressing "OK" on the dialog box will bring you back to the NotePad working window.
• OPENING A TEXT FILE. To open on existing files and to continue working on them, you may do so by selecting the "OPEN" command from the FILE menu. You need to supply the filename of the file you wish to open onthe dialog box.
• QUITTING NOTEPAD. To quit from a running NotePad editor, select the "EXIT" command from the FILE menu by using your mouse.

What is the Internet ?

• The Internet: A collection of host computers around the world that communicate across networks using a common language (protocol).
• Network: Computer equipment and cables that allow hosts to communicate with one other.
• An internet (small i): Any collection of hosts that communicate over a wide area network.
• Protocol: A specification for a manner of communication. The Internet uses TCP/IP as a Protocol.
• TCP/IP: Transmission Control Protocol / Internet Protocol. IP carries individual packets of data from one host to another. TCP makes use of IP and governs the flow of data packets. TCP also provides error checking and correction.
• Host: In general, a single computer system with its own unique name and address. Hosts can be single user or multiuser.
• Server: Any host capable of providing (serving) a service.
• Client: A host requesting a service. A host can be both a client and a server at the same time.
• Service: Any task carried out by a server on behalf of a client. Examples: File services, WWW services and printing services

• Cold war Era in the U.S. (1950s and 1960s)
• Distribution of computer resources is key.
• Computers are large and expensive.
• Shuttle data files from one site to another - cheaper than buying computers for each site.
• 1969 First network: ARPA-NET Advanced Research Projects Agency Network - Connected four computers, 3 in California and one in Utah
• 1975 ARPA-NET becomes a general purpose research network
• 1983 TCP/IP adopted as a protocol standard
• 1983 ARPA-NET and MILNET separated. Both linked together form the "Internet".
• 1990 ARPA no longer funds Internet. Privatization begins.
• Who Owns the Internet now? Phone companies, universities, schools, other companies, individuals...

Purpose: To learn who is using the Internet, what they do with it and where they live

• Currently about 9 million hosts - fairly easy to count (Source: nic.merit.edu/nsfnet/statistics/history.hosts as of 1/96)

• How many people use the Internet? Between 10 and 20 million users depending on who you believe - O'Reilly & Associates survey for example.
• Where are they from? All over the world. Large number are from the U.S. and Western Europe.
• What do they use it for? In the past, academic and military research. Recently, all forms of research (e.g., consumer) and for entertainment.
• How do they access the Internet? In the past, through universities and corporations. Recently, through private providers and major on-line services like Prodigy, Compuserve and AOL. Home PCs can now access the Internet.

Purpose: To learn how hosts on the Internet are individually identified

• Each host on the Internet has a unique Name and Address
• A name is almost always spelled in lower case letters, no spaces, with periods ("Dot") in between.
• Host names are typically broken down into 3 or 4 parts:
  1. A geographic (e.g. country) designation is given at the "highest level" for hosts outside of the U.S.:

       uk   us   ca   au   fr   it   dr   zw
     

  2. An organizational designation may be in place of geographic in the U.S. but can also appear in combinations:

     com    - A commercial company (IBM, Reebok)
     edu    - A school or University in the U.S.
     gov    - A government agency
     mil    - A branch of the military
     org    - A not-for-profit organization
     net    - An organization involved with managing
              the Internet
      

  3. The next level down is the "organizational" level. The actual name of the company, school or organization:

     rutgers    microsoft    pizzahut   planetreebok
     

  4. Within an organization, there may be several individual hosts, each with their own name:

     snoopy    cs     www    eng311pc4    pegasus
     

• These parts are assembled from right to left:

    pegasus.rutgers.edu
    andromeda.rutgers.edu
    www.microsoft.com
    lethe.leeds.ac.uk
    www.whitehouse.gov
    www.planetreebok.com
      
  

• Notice: All lower case letters with no spaces.
• Problem: Computers on the Internet can't memorize all of the possible host names.
• Each host name also has a corresponding number called the Internet Protocol Address or IP Address for short.
• This address is broken into 4 pieces separated by periods.
• Here are the IP Addresses for the hosts listed above:

  Host Name                IP Address
  --------------------     --------------
  pegasus.rutgers.edu      128.6.10.4
  andromeda.rutgers.edu    128.6.10.45
  www.microsoft.com        198.105.232.4 
  lethe.leeds.ac.uk        129.11.244.5
  www.whitehouse.gov       198.137.240.91
  www.planetreebok.com     207.19.162.14
  

• For almost all tools, one can use either the IP address or the host name. If the host name is given, the computer will look up the appropriate IP address for you.

• Definition of the World Wide Web
• Uniform Resource Locators
• Netscape Basics
• Some WWW Exercises
• Tips and Tricks for Using the WWW
• More Topics for This Week

• The World Wide Web or WWW or "The Web": A global collection of documents (called pages) linked together using hypertext.
• Hypertext: Documents that are read by following links of interest to similar topics - as opposed to reading straight through a document from beginning to end.
  • Normally we read a book in a linear fashion. Page 1, then Page 2, etc.
  • With hypertext, we follow our curiosity by skipping around the document(s) using hypertext links.
  Hypertext is made up of three distinct parts:
  1. Text Pages - The text you read.
  2. Anchors - The starting point for a link.
  3. Links - A pointer to another text page.

• WWW Pages are stored on Internet hosts.
• Pages are accessed using a WWW Browser such as Netscape, Mosaic or Microsoft's Internet Explorer.
• Pages can contain text and graphics to be viewed.
• Pages can also contain movies, sounds or animations to be downloaded and viewed.
• Pages are written in the HyperText Markup Language (HTML) - more on this later.
• The address or location of a WWW page is defined by its Uniform Resource Locator or URL.

• URL: A three part name for a WWW or Internet resource:

      protocol://hostname/filename
  

  1. Protocol: The method used to access the resource. Examples:

           http     ftp     gopher     mailto
     

  2. Host Name: The name of the host where the resource is located.
  3. File Name: The directory and file name of the resource.
• In most cases, the method used to access resources (protocol) will be http.
• HTTP: the HyperText Transfer Protocol.

URL Examples

1. http://cimic.rutgers.edu/~holowcza/index.html
         

   HTTP Protocol. Host name is pegasus.rutgers.edu and file is ~holowcza/index.html
   

2. ftp://ftp.std.com/obi/William.Butler.Yeats/Yeats/Balloon
         

   FTP Protocol. Host name is ftp.std.com and the file is obi/William.Butler.Yeats/Yeats/Balloon
   

3. gopher://stis.nsf.gov
              

   Gopher Protocol. Host name is stis.nsf.gov and the root Gopher menu will be shown.

• Notice: All lower case letters with no spaces.

• Netscape Navigator is a WWW Browser from the Netscape Corp.
• We have version 2.02 installed in the Rutgers Labs.
• Netscape runs in MS Windows so we'll be using the mouse quite a bit.
• We will practice with some of the example sites shown above.

Netscape Functions

• Find out how much money it costs to go on a tour of the White House in Washington, D.C.
  1. Pull down the File menu and choose the Open Location menu choice.
  2. Type in the URL for the White House:
     http://www.whitehouse.gov
  3. Press Enter and the White House home page will appear. This might take a minute since we are all accessing the page at the same time.
  4. Scroll down until you see "White House History and Tours"
  5. Click on the icon next to the text there. The White House History and Tours Web page will appear.
  6. Scroll down until you see the text: "If you are coming for a visit, please read this information on White House Tours"
  7. Click on the underlined text. The White House Tour Information Web page will appear.
  8. Scroll down to the first paragraph...

Try the following tasks on your own

• Go to the NASA WWW site and find out when the next shuttle launch is scheduled.
• Go to Rich's WWW home page and find out where he attended college as an undergraduate (Hint: It wasn't Rutgers :)
• Go to the Library of Congress home page and find out what Thomas is and what information Thomas contains.

• A Common Netscape Error message is: Netscape is unable to locate the server: xyz.com Check the server name in the location and try again. One of the following might be the problem:
  1. The host name is misspelled. Check your spelling and try again. Make sure you use lower case letters.
  2. The host is currently not running. Try again at a later time.
  3. The host has been shut down or the site has been moved. Not much you can do.
• Another common Error message: 404 - Not Found In this case, the host is running but it could not find the file you specified. Check the URL and try it again.
• In many cases, these error messages appear because a host changes its configuration such as its name or the location of its files.
• Some things to try:
  1. Try going to the main home page directly. For example, if this URL does not work: http://cimic3.rutgers.edu/music/rich/notes.html Give one of the following a try instead: http://cimic3.rutgers.edu/music/rich/ http://cimic3.rutgers.edu/music/ http://cimic3.rutgers.edu/
• Sometimes you will come across a site that is running very slowly. Very popular Web sites can be bogged down with many requests for pages. Here are some tips:
  1. If the Web page has a lot of images (pictures), it will load very slowly. Try going to the Netscape Options menu and un-checking the Auto Load Images option. This will prevent images from being loaded into your browser. The result may be ugly, but the page will load much faster.
  2. If, while loading a web page, the browser seems to freeze - that is, the netscape logo is doing its thing but the screen is blank, try pressing the "Stop" button (or press the ESCape key). What can happen is that most of the Web page comes in OK but 1 or 2 images remain to be loaded. By stopping the loading process at this point, what has already come across will be displayed and quite often this provides enough information. If the page is unreadable, try loading it again by clicking on the "Reload" button or by pulling down the View menu and choosing the Reload choice.

• WWW Search Engines
• More Netscape Features
• Building your own WWW Pages

What You'll Be Learning About Today

• WWW Search Engines
• WWW Searching Exercises
• More Netscape Features
• More Topics for This Week

Purpose: To learn how to search the WWW using a variety of search engines.

• There have been estimates that as many as 50 million WWW pages are on the Internet.
• A new Web page is created every minute.
• How can you find pages of interest ?
• Answer: WWW Search Engines!
• How does a WWW Search Engine work ?
• First, an Index of Web pages is built:
  1. A special program is written to systematically access every Web page.
  2. The contents of each page are Indexed.
  3. All of the indexes are collected into a database along with the URLs of each page.
• To Search for a Web page:
  1. A user types a few key words related to their topic.
  2. Matching words or phrases are found in the index.
  3. The corresponding URLs are displayed to the user.
• Some search engines are more sophisticated. They include reviews by people who browse the Web every day.

Search engines to try

AltaVista http://altavista.digital.com

Offering compact or detailed searches through what the company claims is the largest Web index, Digital Equipment Corporation's Alta Vista can help you find your way through 8 billion words filling 30 million Web pages. It also provides a full-text index of more than 13,000 newsgroups.

InfoSeek http://guide.infoseek.com

Rated the number one search service by PC Computing, Infoseek Guide helps you find what you're looking for on the Net, for free. With each search, you get the most relevant matches, related topics to explore, and timely news and views from popular magazines, TV networks, and the best online experts. Infoseek Guide also makes it easy to find email addresses, stock quotes, company profiles, and more.

Lycos http://a2z.lycos.com

The Lycos A2Z directory takes a new position in the crowded field of Net directories. A2Z starts with the most frequently linked sites, and adds concise, authoritative descriptions. From the best kids' pages to the world's film festivals, to UFOs and virtual psychics, A2Z has it.

YaHoo! http://www.yahoo.com

Arguably the pioneer Internet guide, Yahoo! has been organizing Web content since what seems like the beginning of it all. Updated daily, Yahoo! allows users to both browse and search subject categories. In addition to using Yahoo!'s search functions, check out up-to-the-minute sports scores, weather, headlines, and stock quotes.

• I've heard about this neat thing called the JASON Project and that there is information about the sunken ship The RMS Titanic on their Web page. Use the InfoSeek Guide search engine to find JASON. Then find out how far down The Titanic sits on the ocean floor.
  1. Pull down the File menu and choose the Open Location menu choice.
  2. Type in the URL for InfoSeek
     http://guide.infoseek.com
  3. Press Enter and the InfoSeek Guide web page will appear. This might take a minute since we are all accessing the page at the same time.
  4. Type in the word JASON in the field provided.
  5. Click on the "Seek Now" button to search.
  6. After a short wait, the results page will appear. Scroll through the results until you see the entry for the JASON Project Home Page Overview.
  7. Scroll down until you see the entry for the RMS Titanic. Click on that link.
  8. A page will appear describing the discovery of the Titanic.
  9. Scroll down to see a list of many more WWW sites devoted to the Titanic.

Try the following search tasks on your own

• Use the InfoSeek Guide to search for information on the Amazon Rain Forest. How large is the Amazon Rain Forest ?
• Use the AltaVista WWW search engine to look for information on the hole in the ozone layer in Antarctica. Find the Environmental Protection Agency's (EPA) "Ozone Home Page". Find out what methyl bromide is and how it harms the ozone layer.
• Use the Yahoo! search engine to find web sites about William Shakespeare.
• Use any of the WWW search engines to look up your favorite music group. See if anyone has set up a Web page about them.

Purpose: To learn some features of Netscape application.

• In the next class, you will begin to learn how to program HTML pages.
• Often you'll come across an interesting page on the Web and you'll ask yourself "...How'd they do that ?"
• There are a few ways to find out...
  1. You can View the HTML "source code" for the Web page.
  2. You can Save the HTML "source code" to a file on your floppy disk.

Try the following exercise

• Search for any music group or singer that you like. Use the search feature of Netscape.
• Keep browsing the pages of your favorite music group or singer until you see an interesting page.
• Once you find an interesting page about your favorite music group of singer. Add the URL of that page into your bookmark.
• View the Source document (the HTML page source code) of the page.
• Print the source code by pulling-down File menu and choose Print
• Go back to the page and save the page into your disk as A:\music.htm
• Print the page.
• Display the page by opening the file you have saved on your disckette.
• Go back to your homepage.
• .........
• Do the same as the above for the topic: "Small Business Development". Note: Use the Magellan search engine. Use the key words such as: "small business", "small business development", or others similar. Find two interesting pages for this and put them in the bookmark.
• Delete all the URL (Pages) from the bookmark list.
• Exit from Netscape.

• Building your own WWW Pages