Searching the World Wide Web From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and...
31
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 1 Searching the World Searching the World Wide Web Wide Web Introduction Introduction • Directories, Search Engines, and Metasearch Engines • Search Fundamentals • Search Strategies • How Does a Search Engine Work?
-
Upload
madeleine-nichols -
Category
Documents
-
view
214 -
download
0
Transcript of Searching the World Wide Web From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and...
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 1
Searching the World Wide WebSearching the World Wide Web
IntroductionIntroduction
• Directories, Search Engines, and Metasearch Engines• Search Fundamentals• Search Strategies• How Does a Search Engine Work?
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 2
Searching the World Wide WebSearching the World Wide Web
Directories, Search Engines, Directories, Search Engines, and Metasearch Enginesand Metasearch Engines
• Directories• Popular Directories• Search Engines• Popular Search Engines• Metasearch Engines• Popular Metasearch Engines• White Pages
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 3
Searching the World Wide WebSearching the World Wide Web
• Hierarchical representation of hyperlinks• Top level of general topics• Sublevels of more specialized subtopics• Easy to use• Not necessary to know exactly what looking for
Directories, Search Engines,and Metasearch EnginesDirectoriesDirectories
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 4
Searching the World Wide WebSearching the World Wide Web
• General directory• Web directory• Web guide• Subject directory• Yahoo! --- www.yahoo.com
• Specialized• Subject guides• Gateway pages• Financial aid resource center --- www.theoldschool.org
DirectoriesDirectories
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 5
Searching the World Wide WebSearching the World Wide Web
• AOL NetFind• CNET Search.com• Excite• Infoseek• Looksmart• Lycos• Yahoo!
Directories, Search Engines,and Metasearch EnginesPopular DirectoriesPopular Directories
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 6
Searching the World Wide WebSearching the World Wide Web
• Computer program:• Accepts form containing query• Searches database• Returns URL• Permits query revision
• Specific• Query syntax
Directories, Search Engines,and Metasearch EnginesSearch EnginesSearch Engines
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 7
Searching the World Wide WebSearching the World Wide Web
• General search engine• Google --- www.google.com
• Specialty search engine• Vertical search engine• Topic search engine• MySimon --- www.mysimon.com
Search EnginesSearch Engines
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 8
Searching the World Wide WebSearching the World Wide Web
• AOL NetFind• AltaVista• Excite• HotBot• InfoSeek• Lycos• WebCrawler• Google
Directories, Search Engines,and Metasearch EnginesPopular Search EnginesPopular Search Engines
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 9
Searching the World Wide WebSearching the World Wide Web
• All-in-one search engine• Call other search engines• Use single query• More matches
Directories, Search Engines,and Metasearch EnginesMetasearch EnginesMetasearch Engines
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 10
Searching the World Wide WebSearching the World Wide Web
• Metasearch• Metacrawler• MetaFind• SavvySearch
Directories, Search Engines,and Metasearch EnginesPopular Popular
Metasearch EnginesMetasearch Engines
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 11
Searching the World Wide WebSearching the World Wide Web
• Information about individuals• Bigfoot• Four11• WhoWhere
• Yellow pages
Directories, Search Engines,and Metasearch EnginesWhite PagesWhite Pages
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 12
Searching the World Wide WebSearching the World Wide Web
Search FundamentalsSearch Fundamentals
• Introduction• Search Terminology• Pattern Matching Queries• Boolean Queries• Search Domain• Search Subjects
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 13
Searching the World Wide WebSearching the World Wide Web
• Information bar• Search form area• Directory area• Links
Search FundamentalsIntroductionIntroduction
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 14
Searching the World Wide WebSearching the World Wide Web
• Search tool• Query• Query syntax• Query semantics• Hit• Match• Relevancy score
Search FundamentalsSearch TerminologySearch Terminology
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 15
Searching the World Wide WebSearching the World Wide Web
• Enter keyword(s)• Search engine returns URLs
Search FundamentalsPattern Matching QueriesPattern Matching Queries
Boolean QueriesBoolean Queries
• George Boole• AND, OR, and NOT
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 16
Searching the World Wide WebSearching the World Wide WebSearch Fundamentals
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 17
Searching the World Wide WebSearching the World Wide Web
• Current web• Newsgroups• Specialized databases• Internet
Search FundamentalsSearch DomainSearch Domain
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 18
Searching the World Wide WebSearching the World Wide Web
• A way to view the search queries of anonymous users in real time• How busy• “Spy” on other users• “See” modifications• Various interests• Personal interests
Search FundamentalsSearch SubjectsSearch Subjects
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 19
Searching the World Wide WebSearching the World Wide Web
Search StrategiesSearch Strategies
• Introduction• Too Few Hits: Search Generalization• Too Many Hits: Search Specialization
Search Fundamentals
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 20
Searching the World Wide WebSearching the World Wide Web
• Determine which search engine to use:• User-friendly interface• Documentation• Conveniently accessible• Database size• Relevancy scores
Search StrategiesIntroductionIntroduction
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 21
Searching the World Wide WebSearching the World Wide Web
• Eliminate keywords• Remove AND or NOT• Enlarge search domain• General keywords• Directory or metasearch engine
Search StrategiesToo Few Hits: Search Too Few Hits: Search GeneralizationGeneralization
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 22
Searching the World Wide WebSearching the World Wide Web
• Add keywords• Add AND or NOT• Capitalize proper nouns• Use first 20 URLs• Directory
Search StrategiesToo Many Hits: SearchToo Many Hits: SearchSpecializationSpecialization
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 23
Searching the World Wide WebSearching the World Wide Web
How Does a Search Engine Work?How Does a Search Engine Work?
• Search Engine Components• User Interface• Searcher• Evaluator• Gatherer• Indexer
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 24
Searching the World Wide WebSearching the World Wide Web
• User interface• Searcher• Evaluator• Gatherer• Indexer
How Does a Search Engine Work?Search EngineSearch EngineComponentsComponents
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 25
Searching the World Wide WebSearching the World Wide Web
• Submit queries• Display results
• Relevancy scores• Matched page summaries
How Does a Search Engine Work?User InterfaceUser Interface
SearcherSearcher
• Program• Searches database for matches
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 26
Searching the World Wide WebSearching the World Wide Web
• Locates URLs• Result set• Factors affecting relevancy score:
• Times query words appear in page• Query words in title• Query words in CONTENT attribute• Number of query words appearing in document
How Does a Search Engine Work?EvaluatorEvaluator
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 27
Searching the World Wide WebSearching the World Wide Web
• Traverses Web• Breadth-first search
• In levels “across” pages
• Depth-first search• Chain of hyperlinks “down”
How Does a Search Engine Work?GathererGatherer
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 28
Searching the World Wide WebSearching the World Wide WebHow Does a Search Engine Work?
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 29
Searching the World Wide WebSearching the World Wide WebHow Does a Search Engine Work?
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 30
Searching the World Wide WebSearching the World Wide Web
• Miscellaneous facts:• Heavy load on Web servers• Restricted depth of searches• Trouble with framed documents• Dependent on collection of documents• Full text indexing
How Does a Search Engine Work?GathererGatherer
From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 31
Searching the World Wide WebSearching the World Wide Web
• Organizes (indexes) gathered data• URL• Document title• Descriptive keywords
How Does a Search Engine Work?IndexerIndexer
