The Internet: How search engines index and rank pages. Sources: How Search Engines Rank Web Pages By

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The Internet How search engines index and
rank pages.Sources How Search Engines Rank
Web PagesBy Danny Sullivan, Editorhttp//searchen
ginewatch.com/webmasters/article.php/2167961
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Question 1

• What is the difference between a search engine
  and a directory?

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Search Engines

• Search engines, such as Google, create their
  listings automatically. Search engines crawl the
  web, then people search through what they have
  found.

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• If you change your web pages, search engines
  eventually find these changes, and that can
  affect how you are listed. Page titles, body copy
  and other elements all play a role.

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Directories

• A directory such as Yahoo depends on humans for
  its listings.
• You submit a short description to the directory
  for your entire site, or editors write one for
  sites they review. A search looks for matches
  only in the descriptions submitted.

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Question 2

• List and define the three major elements of a
  search engine?

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Part I

• Search engines have three major elements. First
  is the spider, also called the crawler. The
  spider visits a web page, reads it, and then
  follows links to other pages within the site.
  This is what it means when someone refers to a
  site being "spidered" or "crawled."

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Spider -continued-

• The spider returns to the site on a regular
  basis, such as every month or two, to look for
  changes.

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Part II The Index

• The index, sometimes called the catalog, is like
  a giant book containing a copy of every web page
  that the spider finds. If a web page changes,
  then this book is updated new information.

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Part III Search engine software

• Search engine software is the third part of a
  search engine. This is the program that sifts
  through the millions of pages recorded in the
  index to find matches to a search and rank them
  in order of what it believes is most relevant.

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Question 3

• Why does the same search conducted on different
  search engines yield different results?

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Question 3

• All search engines have the basic parts described
  above, but there are differences in how these
  parts are tuned. That is why the same search on
  different search engines often produces
  different results.

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Question 4

• How do search engines rank pages?

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How Search Engines Ranks Pages

• So how do search engines go about determining
  relevancy?
• They follow a set of rules, with the main rules
  involving the location and frequency of keywords
  on a web page. Call it the location/frequency
  method, for short.

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Location, Location, Location...and Frequency

• Pages with keywords appearing in the title are
  assumed to be more relevant than others to the
  topic.
• Search engines will also check to see if the
  keywords appear near the top of a web page, such
  as in the headline or in the first few paragraphs
  of text.
• They assume that any page relevant to the topic
  will mention those words right from the
  beginning.

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Spice in the Recipe

• Frequency is the other major factor in how search
  engines determine relevancy.
• A search engine will analyze how often keywords
  appear in relation to other words in a web page.
• Those with a higher frequency are often deemed
  more relevant than other web pages.

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Indexing

• some search engines index more web pages than
  others.
• Some search engines also index web pages more
  often than others.
• The result is that no search engine has the exact
  same collection of web pages to search through.

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Popularity

• Search engines may also give web pages a "boost"
  for certain reasons.
• Some search engines use link popularity as part
  of its ranking method. It can tell which of the
  pages in its index have a lot of links pointing
  at them.
• These pages are given a slight boost during
  ranking, since a page with many links to it is
  probably well-regarded on the Internet.

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Reviews

• Some hybrid search engines, those with associated
  directories, may give a relevancy boost to sites
  they've reviewed
• The logic is that if the site was good enough to
  earn a review, chances are its more relevant
  than an unreviewed site.

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Meta Tags

• Meta tags are what many web designers mistakenly
  assume are the "secret" to propelling their web
  pages to the top of the rankings.
• Some do give a slight boost to pages with
  keywords in their meta tags. read them at all,
  and there are plenty of examples where pages
  without meta tags still get highly ranked. They
  can be part of the recipe, but they are not
  necessarily the secret ingredient.

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Spamming

• Search engines may also penalize pages or exclude
  them from the index, if they detect search engine
  spamming.
• An example is when a word is repeated hundreds of
  times on a page, to increase the frequency and
  propel the page higher in the listings.
• Search engines watch for common spamming methods
  in a variety of ways, not the least by following
  up on complaints.

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Question 5

• Define the following terms

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Bookmark/favorite

• Bookmark - A page on the Netscape Browser that
  lists URLs or Web addresses. Bookmarks serve as
  links for easy access to Web addresses. MS
  Explorers equivalent is called Favorite
  Places..

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Bookmark/favorite

• To bookmark a Web page on your screen, click
  Bookmark on the bar, and when it is displayed,
  click Add Bookmark. The link then adds to the
  bottom of the Bookmark Listing.

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Boolean Search

• Boolean Search - A keyword search that uses
  Boolean Operators for obtaining a precise
  definition of a query. See Operators Used In
  Keyword Searches in Section B
• and, or, not etc..

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Browser

• Browser - A computer program used to connect to
  Web sites on the World Wide Web and access
  information.
• Examples Netscape Navigator, Microsoft Internet
  Explorer.

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Directory Search

• Directory Search - A hierarchical search starts
  with a general heading and proceeds through
  selection of increasingly more specific headings
  or subjects.

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Directory Search

• It provides a means of focusing more closely on
  the object of the search. It is also referred to
  as subject search, directory guide or directory
  tree.

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Home Page

• Home Page - The first page of a search tools Web
  site.

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Hypertext Link

• Hypertext Link - A highlighted word or image
  shown in color on a Web page that when clicked
  connects or links to another location with
  related information. Links provide an easy way
  to move about the Internet.

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Internet

• Internet - The Internet, with a large I, refers
  to a worldwide system of linked computer networks
  that serve as a communication system. When used
  with a small i, a term used to mean a group of
  interconnected local networks.

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Keyword Search

• Keyword - A term that a computer can recognize
  and use as the basis for executing a search.
• Keyword Search - A search that utilizes terms
  that defines the users interest.

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Query

• Query - A search request. A combination of words
  and symbols that defines the information that the
  user is seeking. Queries are used to direct
  search tools to appropriate Web sites to obtain
  information.

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Ranking

• Ranking - A means of listing hits in the order of
  their relevancy. It is usually determined by some
  selection of the number, location and frequency
  of the term in the document being searched.

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Search Engine.

• Search Engine - A host computer that serves a Web
  site and provides information from within its own
  sites and via links with other Web sites. This is
  accomplished by using the keywords of a query to
  match index terms in the search engines
  database.

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Search Tool

• Search Tool - A computer program which conducts a
  search on the World Wide Web.

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URL

• Uniform Resource Locator URL -Uniform Resource
  Locator is the Internet designation of a Web
  address.

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WWW

• World Wide Web WWW or the Web - A global
  computer communication system that uses the
  Internet to transmit data i.e. text, numbers,
  images and sound.

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Question 6

• What is a meta-search? How does it work?
• A multi-engine search, also called a meta-search,
  utilizes a number of search engines
  simultaneously.

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Metasearch

• The search is conducted via keywords employing
  commonly used operators or plain language. It
  then lists the hits either by search engine or by
  integrating the results into a single listing.
• Tip Use to speed up the search process.
• Advantage Often provides fewer references and is
  tolerant of imprecise search questions.
• Disadvantage Can not be used as effectively as a
  search engine to conduct difficult searches.

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Question 7

• How are the following notations useful in search
  engines that have a common set of operators? ,
  -, " , AND, OR, NOT.