Power Surfing the Net

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Power Surfing the Net

• (Using Search Engines with Maximum Effectiveness)

Part One Search Engine Spectator Sports
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Table of Contents
Part One Search Engine Spectator Sports

• 1. What is a Search Engine?
• 2. But Could You Pick One Out of a Lineup?
• 3. Under the Hood of a Search Engine
• 4. Gentlemen, Start Your Engines!

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Part One Objectives
PART ONE HAS SEVERAL LEARNING OBJECTIVES

• Understand What a Search Engine Is
• Understand What a Search Engine Does
• Recognize Common Key Features of Search Engines
• Learn How Search Engines Work
• Learn How to Start a Search Engine

Part One will leave you a competent but casual
Search Engine user
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1. What is a Search Engine?
A search engine explores sites and catalogs them
for your use.

• A Search Engine is a software program.
• Its function is to locate information on the
  Internet.
• Search engines are funded by collecting money
  from advertisers, Web Authors and/or Web surfers
  like you!
• There are hundreds of different Search Engines,
  such as NorthernLight, AltaVista, Yahoo, Excite,
  Hotbot, Infoseek, DogPile, Metacrawler, ...

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2. But Could You Pick One Out of a Line-Up?
candy

• Every Search Engine looks a little
  different
• But all have 4 key features in common
• Search Entry Field
• Search Start Button
• Search Help Support
• Results Display

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The Search Entry Field

• In the example below, the Search Engine Excite is
  being used to locate recipes for Brownies. In the
  Excite Search Entry Field, a user has typed in
  the topic for which they are searching Brownies!
  
  

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The Search Start Button

• Once you have typed your search topic into the
  Search Entry Field, you need to tell the search
  engine to begin its search.
• This is done by clicking on a search start
  button.
• Here are some start buttons from various search
  engines

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Search Help Support

• Every search engine provides on-line help.
• The Help feature describes how to use a
  particular search engine most effectively.
• If you are doing a serious search, READ THE
  HELP FILES OF WHATEVER SEARCH ENGINES YOU
  USE!! Heres an example

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On-Line Search Help

• Since every Search Engine performs in a slightly
  different way, and continues to add new feature
  content, it is important to regularly read the
  on-line help section.

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Results Display

• When a Search Engine has completed its search, it
  will display the results.
• Results are typically shown as a number of web
  page matches or hits, often with some sort of
  ranking.
• Heres the result of a search for chocolate cake

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It Works Something Like This...

• Imagine this -- make a big table, with lots of
  columns and lots of rows.
• In the left most column, make a row entry for
  every word in the dictionary.
• Now, start reading a Web Page from the Internet,
  like this page about Ants.
• For every word you read on the page, make an
  address entry to show that the word appears at
  the site.

www.ant.com Welcome to the Ant Web Page! Ants are
tiny bugs. They come in many varieties -- red
ants, fire ants and black ants. They love
picnics...
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Now Keep Goin

• The site about ants includes active links to some
  other sites, such as picnics and black ants.
• You will need to index these sites, in the same
  way that you indexed the ant site.
• When you read these sites, you learn an
  astounding thing These sites mention ants!
• So the addresses of these sites are added to the
  row on ants
• And by the way, these sites also have active
  links to other sites, such as bugs and insects
  and red ants and fire ants and pygmy ants and
  on and on. (You need to index these sites, too)

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And Dont Stop Yet

• Now, repeat this process for lots and
  lots of sites, and you will have built up a
  list of indexed web pages.
• Your list will be huge.
• Back to the ants there will be an address
  listing for every site you read that mentions
  ants.

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Now, Do a Search ... With the Hood Up!

• When you ask a Search Engine to look for a
  particular topic, it doesnt search the Internet.
• Instead, it searches its list of indexed sites.
• The results are similar to a listing of all the
  web page addresses from all the columns to the
  right of your search topic.

A search for ant will result in addresses for
www.ant.com, www.picnic.com,
www.fireant.com . Along with every other
column to the right beyond the displayed three!
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The Chicken and Egg Problem

• We did gloss over one problem -- How to get
  started
• In our example, we already knew the address of
  our first site (www.ant.com)
• How do search engines get started? How do they
  know where to find new sites to index and add to
  their list?
• Search engines build indexes using two broad
  construction strategies.
• In the past, each search engine followed one of
  the two strategies, but now most engines use a
  combination of both.

Which came first? The Web address or the index?
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Getting Your Engine Built

• Most search engines today use a combination of
  two construction strategies to create and
  maintain indexed lists.
• Directories are lists maintained by
  Administrators, and divided into hierarchical
  topic categories.
• Spider programs are software programs that
  automatically crawl the net looking for sites and
  indexing those they find.

Building up that search engine.
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Construction by Directory

• On the left is an example of a predominantly
  Directory managed Search Engine
• Notice that the list is divided into subject
  categories, with sub-categories underneath
• Search Engine employees read, index and file
  sites within the appropriate categories

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Construction by Directory

• To be listed on a predominantly Directory managed
  Search Engine, a Web Author sends a message to
  the Search Engine Administrator, asking to be
  included on the Search Engines list of indexed
  sites.
• This is usually, but not always, an E-mail
  message
• Along with a site address, the author submits a
  brief site description
• The administrator ensures that the site is read
  and indexed, and then the site is added to the
  search engine list within the appropriate category

Dear Administrator, Enclosed is my Web Page on
Ants. Please include it in your Search Engine
List under BUGS. It will make my Mother proud!
THANKS!
ANTS
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Construction by Spider

• Spider Programs are automated software programs
  that crawl the Web all the time.
• They index a site, then crawl to its active
  links.
• They index those sites, then crawl to those
  sites active links.
• And on and on...

The AltaVista spider has been give a marketing
name Scooter!
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Construction by Spider

• To be listed on a predominantly spider driven
  search engine, a Web Author submits a site
  address to the search engine.
• The spider receives this address, and crawls to
  the site to index it.
• The process of indexing the site adds its address
  to the Search Engines list of indexed sites.

Dear Spider, Here is my web site address.
www.ant.com Welcome to the Ant Web Page! Ants are
tiny bugs. They come in many varieties -- red
ants, fire ants and black ants. They love
picnics...
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Spamming the Spider

• The automation of indexing by spider allows for
  some technical trickery.
• Some Web Authors realized that they could insert
  irrelevant but popular words on their web pages.
• These words could even appear hidden by making
  them the same color
  as the background page.
• While hidden to users, they would be read by
  spiders and
  processed in the indexing.
• In this way, people could be tricked into
  visiting sites.
• This is a form of Spamming, and can get you
  into serious
  trouble with Search Engines .
• (HEY, what kind of jerk would try to trick
  Scooter,anyway?)

www.ants.com
Ants are bugs. There are lots of ants black,
red, fire, pygmy, etc. Ants like to come to
picnics. Ants make good pets in Ant Farms.
Sex, money, Oprah Winfrey
Spider Spamming
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(Of Course, Its Not Quite That Simple)

• The Internet grew astronomically, and two events
  occurred
• (1) Many Search Engine managers decided it was
  not cost effective to index an entire site. Some
  Engines began indexing just the first paragraph,
  or even just the title. Even so, the search
  engines stay pretty busy given how many new Web
  pages come on line each day.
• (2) User research concluded that most surfers
  only look at the first ten hits reported in a
  search. This led to changes in the behavior of
  Search Engines and Web Authors.

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Dick Clark Was Right All Along!

• When user research established that most Internet
  surfers never look beyond the first ten hits, the
  contest was on
• Internet surfers complained that they wanted some
  way of sorting through long lists of hits
• Investors funding a Web Page wanted to make
  certain that their site made it to the Top Ten!
• Search Engine managers responded to this consumer
  pressure by developing formulas for ranking
  search hits.
• The highest ranking sites are displayed
  first.

It's A Top Ten Countdown!
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Breaking Into the Top Ten

• Search Engines use formulas to determine how
  lists get ranked
• Each Search Engine uses a slightly different
  formula
• The exact formulas are a part of market place
  distinction for each search engine
• Despite the differences, some general ranking
  trends exist

The Top Ten Countdown Continues!
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Formula 10 Winners

• Site Traffic
• A count of how often a site has been visited.
• Theory Marketplace consumer voting (if a lot of
  people have visited the site, it must be a good
  site)

• Key Word Count
• A count of how often key words are repeated at a
  site.
• Theory Repetition of a key word is a measure of
  site emphasis
• (So the next time you are docked for repetitive
  word usage, tell your teacher you are publishing
  on the Net )

And there's more!
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Formula 10 Winners

• Title and Top
• A count of how often key words appear in the
  title and sometimes the introductory paragraph.
• Theory Titles describe Web Pages, and
  introductory paragraphs define what follows.

• Weighted Proximity
• A count of how often key words appear within some
  specified (word) distance of each other
• Theory Sites that use your key words in the same
  sentence will be more relevant than those that
  dont.

And more!
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4. Gentlemen, Start Your Engines!

• Well -- now we know what a Search Engine is, what
  it does, and how it works.
• Lets use one!
• Search engines are software programs that are
  located at Web pages
• To start a Search Engine, you simply visit its
  site
• So -- start your Internet Browser ( such as
  Netscape Communicator, Internet Explorer, etc.)
  and LETS GO!!!
• Hey, I meant it! Point the cursor on the racecar
  to get going!

Click here advance to next slide
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Starting A Search Engine

• Starting a Search Engine has become simpler -
  Browsers now have search buttons that allow you
  to select a Search Engine. Heres Internet
  Explorers Search Feature

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Starting A Search Engine

• Once you start a Search Engine, you can bookmark
  its address for future use.
• Or, if you know the address of a Search Engine,
  you can always type its URL in the Browser
  address field
• Below, the Internet Explorer browser is being
  used to start the Yahoo Search Engine
• If you have to guess at the address of a Search
  Engine, try
• www.searchenginename.com

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Part One Summary

• Search Engines are software programs that build
  up lists of indexed Web pages, either in
  administered directories or by spider crawled
  sites.
• Searches are actually performed against indexed
  lists, not against the Internet itself
• While there are hundreds of engines, some common
  operational features exist
• (Search entry field, search start button, online
  help and results display)
• Because there is so much information on the
  Internet, Search Engines use formulas to rank the
  sites found in a search. Each search engine uses
  a different formula.
• Search Engines are located at Web Sites and can
  be started from Web Browsers

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Part One Skill Assessment

• You should now complete Lab One for a hands-on
  reinforcement of the concepts introduced in Part
  One.
• Then, you should complete the online test for
  Part One.
• (Remember, these tests are not recorded -- they
  are simply a study aid for you.)
• See you in Part Two!