Using the Internet

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Using the Internet
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What is the INTERNET

• there are a large number of computer networks
  around the world like the one we have here at
  this University
• these networks are interconnected and they form
  the INTERNET
• the main Australian link of the INTERNET is
  called AARNET (Australian Academic and Research
  NETwork)

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Short history of the Internet

• late 1960s United states military started the
  network of computers
• 1973 Britain and Norway joined the ARPAnet (40
  computers)
• 1992 WWW born
• 1993 Mosaic and Netscape arrived
• 1999 approx 800 million users worldwide

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WORLD WIDE CONNECTIONS
USERS SCHOOLS BUSINESS Students
ONLINE SERVICES
WORLD
PHONELINES cable TV satellites
MODEMS
INTERNET SERVICE PROVIDERS
BUSINESS INTRANETS
FIREWALLS
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What is the Information Superhighway

• the Infobahn / Information Superhighway is what
  it is expected the INTERNET will become as its
  carrying capacity is increased by fiber optics
  cable.(BAND WIDTH)
• the INTERNET has in the past been basically for
  academic and research use, the Information
  Superhighway will have much more commercial and
  entertainment use

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What can the INTERNET do?

• allows you access to large amounts of information
  stored on computers around the world. ( world
  wide web)
• allows you to contact and exchange ideas with
  people around the world quickly and efficiently.
  (E-Mail and IRC CHAT)
• allows you shop from around the world .
  (Electronic shopping)

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Tools to surf the INTERNET

• two groups of tools -- text based and graphics
  based
• text based tools
• FTP (File transfer protocall)
• telnet (logs on to other computers)
• graphics based BROWERS
• Netscape, Microsoft explorer

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What do you need to surf the Net

• There are a few ways to access the Internet
• a direct connection (eg.via the universities
  local network)
• a dialup connection at home (via a modem) through
  a Service Provider
• via a Internet Cafe in Adelaide
• Via cable modem television

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Connections for BIL students

• universities have a direct connection to AARNET
  and so any computer connected to the universities
  network is automatically connects you to the
  Internet for the semester
• Email accounts are also on the Internet
• All transactions are logged
• World access for registered users

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Main Internet Software

• Microsoft Outlook --- used first for email
• Netscape --- Used to search World Wide Web
• Microsoft explorer --- Used by Microsoft
  Corporation to compete with Netscape

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World Wide Web Software

• Netscape is on this system and is your
  access to the W orld Wide Web
• World Wide Web sites has a home page
• The Homepage connected to other pages by Hotlinks
• Other Web sites obtained by typing in the
  address of the Website

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Internet address (URL)

• Uniform Resource Locator
• World Wide Web Http//www.CNN.com
  Http Hyper text
  transport Protocol.
  www. world wide web.
  CNN Consolidated news network
  com
  commerical domain
• Email is Andrew.Barr_at_UNISA.edu.au name at
  university. education.Australia

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Internet Terms

• ISP Internet services providers makes a local
  phone connections (price varies)
• Web servers are computers with big files of
  information responding to your requests.
• Online services are companies that sell specific
  information like flight bookings or books

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World Wide Web

• Millions of web pages stored on computers around
  the world
• Text ,pictures, sound, animation, video.
• Links with other pages via hypertext allows
  interaction,
• Find information by search engine or index

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Internet-- the next generation

• By year 2000 - more people on internet than TV
  because of digital change.
• 80 of Australians have a PC in 1999
• Global network of computers - replacing the
  Telephone and Television.
• Internet the new Mass medium
• 500 pay TV channels vs 1,000,000 internet
  channels

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Internet--GLOBAL VILLAGE

• New Internet Mass Media allows INTERACTIVITY
• New Internet Mass media allows VIRTUAL
  REALITY
• New Internet Mass Media allows COMMERCE

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Search Engines
Information
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Problems with searching the Web

• Unregulated growth
• no standard indexing
• slow response time
• no validity check (peer review?)
• No way to determine if changed since last
  accessed site
• no way to reject irrelevant documents

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Many Search engines

• Search Engines are Computer programs
• They move through the Web collecting
  Key-words
• On - screen directions are easy to follow
• Results presented as a list of sites
• Ranked in order of relevance

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Four types of search engines

• 1.SUBJECT Directories like Yahoo.com.au
• 2.AUSTRALIAN search tool like Anzwers.com.au
• 3.META SEARCH Tool like Dogpile.com.
• 4. KEY WORD search like Altavista.yellowpages.com.
  au

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Relevance and Ranking

• Relevance due to a formulae
• Each search engine is different
• Assign weight to keyword position
• Produce the results list in rank order
• There is a lot of junk as well

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Search engines vary

• How often is it updated?
• (FULL TEXT) Key word in Title of Homepage?
• Some search engines only record home pages
• Some search engines also search the LINKS!
• For speed Use a multiple search Engine

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Broadening a full text search

• Keywords are important
• The use of synonyms (thesaurus)
• The use of Boolean system OR
• Use of Truncates as Walk (for walkers,
  walkabout, walking)
• receive too many HITS

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Broadening a search

• Example

Keyword Results Caving 926 Cave
exploration 44 cave Explor
88 Caving OR cave ex 977
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Narrowing a FULL TEXT search

• Use very specific terms
• Use Boolean AND between words
• Request keyword in title
• Add another concept (such country or date)
• each search engine has an advanced feature
• Use the online HELP

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Narrowing a FULL TEXT search

• Example

Keyword Results biotech research
300,000 biotech research
3,000 Title biotech and Titleresearch
100 Title biotech research AND Europe 3
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Multiple Search Engines

• Http//www.dogpile.com
• Uses 15 independent search engines
• http//www.search.com
• Access to 470 databases
• http//www.webtaxi.com
• 12 most popular and Access to supersearch

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The Internet
Prepared by Andrew Barr