• 3 Main Types of Search Tools
• Components of search engine
• Step used on searching
• Popular Search Engines
Search engine is a software program
that searches for sites based on the
words that you designate as search
Search engines look through their own
databases of information in order to
find what it is that you are looking for.
Archie – First search tool for the Internet
Gopher – indexed plain text documents
Jughead – searched the files stored in
Gopher index systems
Wandex – first Web search engine
3 Main Types of Search Tools.
Web Directory - Hierarchical organized in a classification
Standard Search Engine – uses
mathematical algorithms and
boolean searches for keyword
Expert Pages – reviewed list.
Components of search engine.
Spider : Program that transverses the web from link to
link to link by identifying the reading pages.
Indexing Software : Program that analyses web
pages downloaded by spider.
Database : Warehouse of the web pages downloaded
Search engine mechanism: Software that enables
users to query the index and that usually returns in
terms of relevancy ranked order.
Step used on
• Web spider gather information about what is available on
the Internet . It sends the address of the document back to
search engine’s indexing software.
• Indexing software extracts information from the document
and organize it into a database.
• When the user visits the search engine’s web page, they
launch a search of its database by typing the keywords
that describe the information they look for.
•Search engine looks for the keywords in the index of the database.
It creates a new web page displaying the URLs and titles of the
•To go to the actual page the users just have to click on the link.
•You’re probably already familiar with search engines such as
Yahoo, Google, Excite, or Alta Vista etc.
Popular Search Engines
Most Popular Search Engines
All the Web, AltaVista,
Gigablast, Ask Jeeves, Dogpile,
Google, HotBot, Metacrawler,
LookSmart, Lycos, MSN
Search, Netscape Search,
Teoma, WiseNut and Yahoo!
Most popular search engine &
searches greatest number of
pages (3.3 million)
Special features include
Advanced search, Image,
Froogle, Blogger, Google
Search engine plays important role in accessing
the content over the internet, it fetches the pages
requested by the user.
It made the internet and accessing the
information just a click away.
The need for better search engines only increases
The search engine sites are among the most