Search Engines

The presentation at the SKYPE conversation conference on 27^th August 2008

Search Engine ≈ a Web search engine

public Websearching for information on the

How it works

Ø Web crawling: Web crawler or spider (sometimes ”robot.txt” ) follows every link it sees and:

· analyses content of each page for indexing it

· stores the data about the content in an index database

Ø Indexing: Types of indices include

· Suffix tree – built by storing the suffixes of words

· Tree – an ordered tree data structure that is used to store an associative array where the keys are strings

· Inverted index – a list of occurrences of each atomic search criterion

· Citation index – citations or hyperlinks between documents

· Ngram index – sequences of length of data to support other types of retrieval or text mining

· Term document matrix

Ø Searching:

· A user makes a query based on key words

· A search engine looks up an index and provides a listing of the best matching web pages (hits)

Key words can be connected by Boolean operators AND, OR, NOT.

Proximity search (an advanced feature) means better results of searching

The most popular search engines (as of 2006)

¨ Google – rose to prominence in about 2001 – 49.2 %

¨ Yahoo! – 23.8 %

¨ MSN – 9.6 %

¨ Baidu – for ideographic writing

¨ Yandex – a search engine for Russian written web pages – 1 %

Meta Search Engines

Ø A user makes a query in the same way

Ø A meta search engine sends it to a non meta search engine

Dog Pile = meta search engine

SEO – Search Engine Optimization

It is the process of configuring a website for maximum exposure

to search engine spiders.

Everything about the design and construction of your website should be done with an eye to search engine performance.

Search Engine Optimization is not a onetime event. It is an ongoing process. A successful Search Engine Optimization strategy begins with proper website design, and carries on incorporating a regular SEO service

Several Free SEO Tools

The SEO Analysis tool (see detailes on http://www.metamend.com/) examines your website from top to bottom, and reports back a record of optimization points you should address for success in the search engines. One of the SEO Analysis tool’s key functions includes a keyword density analyzer that shows you how well your site is utilizing valuable terms.

The Keyword Density Analyzer (see detailes on http://www.metamend.com/) is a powerful free SEO tool that shows you how well your site is utilizing valuable terms.

The Search Engine Spider simulator (see detailes on http://www.metamend.com/) will scan your web page and display the content that is read by the major search engines. Then it displays the Search Engine Friendly links found on the web page to show how many pages will be sucessfully ’spidered’ (crawled and indexed).

Prepared by Galina Vitkova