This document provides an overview of search engines, including what they are, their importance, types of search engines, and how to use them effectively. It defines a search engine as a software system that searches the web using keywords and ranks results by relevance. It explains that search engines are important because they help filter the vast amount of online information to quickly find specific information. The document outlines different types of search engines such as crawler-based like Google and Yahoo, directories, hybrid, and meta-search engines. It concludes by giving tips for using search operators like +, -, quotes, and or to refine searches.

1. Presented by
Rony and Samantha

3. Contents….
 what are search engines
 Importance of search engines
 Types of search engines
 How to use search engines effectively

4. What are search engines???
 A web search engine is a software system
that is designed to search information on the
world wide web
 It uses keywords to search for the
documents and puts the result in order of
relevance to the topic that was searched for

5. Some examples of search engines

6. Importance of search engines…!!
 Search engines are important because with over 8
billion WebPages available ,it would be
impossible to search for the information that is
specifically needed.
 This is why search engines are used to filter
information that is on the internet and transform it
into results that each individual can easily access
and use within seconds.

7. Types of search engines
 Crawler based search engines
 Directories
 Hybrid search engines
 Meta search engines

8. Crawler based search engines
 These type of search engines use a spider or a
crawler to search the internet.
 The crawler digs through individual WebPages,
pulls out keywords and adds the pages to search
engine’s data base
 Google and Yahoo are examples of crawler search
engines
 Crawler based search engines are good when you
have a specific search topic.

11. Search window of….

12. Directories..
 Directories depends on human editors to create
their listings or database
 Yahoo directory, open directory and look smart
are some examples.
 Human directories are good when you are
interested in a general topic of search.

13. Yahoo directory

14. Hybrid search engines
 Hybrid search engines are those search engines
that use both crawler based searches and directory
searches to obtain their result
 Example: yahoo.com, google.com

15. Meta-search engines
 These transmit user-supplied keywords simultaneously
into several individual search engines to actually carry out
the search
 Search results returned from all search engines can be
integrated, duplicates can be eliminated, and additional
features such as clustering by subjects can be implemented
by meta search engines.
 Ex:dogpile,metacrawler

17. How to use search engines??
+
• A “+” before the word in search will locate for documents which
definitely contain the word
-
• A “-” before the word will exclude that word from the search
“ ”
• Placing words between quotation marks will search for the phrase
between the quotes.
or
• Using “or” between search words will search each term separately.