Introduction to search engine

1. Search Engine
Ankush Srivastava
Search Engine
MCA VI Semester
Dept. of Computer Science
University of Lucknow
Lucknow.

2. Searching
What is searching and what we search?
Search Engine
Somewhere in a collection of documents, Web pages, and other
sources, there is information that we want to find, but we have no
idea where it is. The searching process give us the means of finding
that information.

3. Types of Search
Engines
Search Engine
 Web-Based Search Engines
 System-Based Search Engines

4. System Based Searching
Search Engine
 Its complete indexing of all the files in the computer like
documents, texts, music, pictures etc.
 The program allows text searches of a user's needed
files.
 For Example Google Desktop.

5. Web Based Searching
 A web based searching is designed to search information on the internet or
World Wide Web.
Search Engine
 For Example Google, Yahoo etc.

6. Types of Search
Engine
• Crawler-Based
Search Engine
• Directories
• Hybrid Search Engines
• Meta Search Engines
• Paid Inclusion
• Specialty Search Engines

7. Crawler-Based
 Crawler-based search engines use automated software programs
to survey and categories web pages. The programs used by the
search engines to access your web pages are called
‘spiders’, ‘crawlers’, ‘robots’ or ‘bots’.
 A spider will find a web page, download it and analyses the
Search Engine
information presented on the web page. This is a seamless
process. The web page will then be added to the search engine’s
database.
 Crawler-based search engines are constantly searching the
Internet for new web pages and updating their database of
information with these new or altered pages.
 Eg:- Google

8. Directories
A ‘directory’ uses human editors who decide what category the site
belongs to; they place websites within specific categories in the
‘directories’ database. The human editors comprehensively check the
website and rank it, based on the information they find, using a pre-
defined set of rules.
Search Engine
For eg:
Yahoo Directory (www.yahoo.com )
Open Directory (www.dmoz.org )

9. Hybrid Search
Engines
Hybrid search engines use a combination of both crawler-based
results and directory results. More and more search engines these
Search Engine
days are moving to a hybrid-based model. Examples of hybrid search
engines are:
Yahoo (www.yahoo.com )
Google (www.google.com )

10. Meta Search Engines
Meta search engines take the results from all the other search
engines results, and combine them into one large listing. Examples of
Meta search engines include:
Search Engine
Metacrawler (www.metacrawler.com )
Dogpile (www.dogpile.com )

11. Paid Inclusion
Most directories offer some form of paid inclusion. Paid inclusion
Search Engine
guarantees your website gets reviewed and/or indexed promptly.

12. Specialty Search
Engines
Specialty search engines have been developed to cater for the
demands of niche areas. There are many specialty search engines,
including:
Search Engine
Shopping
- Froogle (www.froogle.com )
- Yahoo Shopping (www.shopping.yahoo.com )
Local Search
- NZPages (www.nzpages.co.nz )
- SearchNZ (www.searchnz.co.nz )

13. Domain Name Search
- iServe (www.iserve.co.nz )
- Freeparking (www.freeparking.co.nz )
Search Engine
Freeware & Shareware Software Search
- Tucows (www.tucows.com )
- CNET Download.com (www.download.com )

14. List of top Search
Engines
1.- Google
2.- Yahoo
Search Engine
3.- Bing
4.- Ask
5.- Aol
6.- AltaVista
7.- Fast
8.- Gigablast
9.- Netscape search
10.- Snap.com
11.- Search.com