WHAT IS A SEARCH ENGINEWHAT IS A SEARCH ENGINE

• A search engine is not a physical engine, instead its an electronic code or a software programme that searches and indexes millions of web pages.

• The programme runs ceaselessly hour after hour, collecting information and cataloguing it

Spidering (crawling)• This activity, (mysterious web code) roams across

millions of websites that form the WWW, to note and record the keywords stored between meta tags in the source code, it then scans

1) The important stories hosted on the home page & record them against the site’s web address

2) opens each links on the home page, records the first few lines of information hosted on hyperlinked pages

3)Then proceed to record keywords stored in the source code of inside pages

A SEARCH ENGINE’S OPERATIONS CAN BE BROKEN INTO THREE CLEAR AREAS:

A SEARCH ENGINE’S OPERATIONS CAN BE BROKEN INTO THREE CLEAR AREAS:

Index• The pages scanned by the spider are stored in a giant

index, the second part of the search engine,

• Since the pages scanned can run into millions, the index can spread across hundreds of servers

• The spider updates the stored info every time it returns to the site.

A SEARCH ENGINE’S OPERATIONS CAN BE BROKEN INTO THREE CLEAR AREAS:

A SEARCH ENGINE’S OPERATIONS CAN BE BROKEN INTO THREE CLEAR AREAS:

A SEARCH ENGINE’S OPERATIONS CAN BE BROKEN INTO THREE CLEAR AREAS:

A SEARCH ENGINE’S OPERATIONS CAN BE BROKEN INTO THREE CLEAR AREAS:

Search Code• The third component of the search engine

• The search code sifts through millions of pages stored in the index to find keywords that match user’s query

• The search code also assigns ranks to websites

STANDARD WEB SEARCH ENGINE ARCHITECTURE

crawl theweb

create an inverted

index

Check for duplicates,store the

documents

Inverted index

Search engine servers

userquery

Show results To user

DocIds

What a Search Engine Sees

• View > Source (HTML code)

• http://www.delorie.com/web/lynxview.html (HTML text, no images and little formatting)

PARAMETERS TO DECIDE A SITE’S RANKPARAMETERS TO DECIDE A SITE’S RANK

Different search engines use different parameters

• Some look at the title of the page

• Others scan the top half of the stored webpage

• And others look for keywords

• And some rank sites on the basis of the number of site links, both external & internal

• Search engine popularity depends on number of pages spidered by the crawler and the ranking parameters employed by the search engine

• The user is more concerned with relevance, accuracy, and précised search

HOW TO GET BEST SEARCH RESULTSHOW TO GET BEST SEARCH RESULTS

• Use precise or specific keywords

• Place search words within quote marks, this binds the words into one single unit

• Use Boolean expressions ( and, or, not , +, -)

• Example:

• Oxford+ university + press

• Oxford +university-press

GENERATING MORE TRAFFICGENERATING MORE TRAFFIC

Rules to be kept in mind while writings meta tags

• Page description must be shorter

• Page description must be precise, must accurately reflect the spirit of the content

• Keyword must be used to reinforce (and should match) the sentence used to describe page content

• No of keywords should be limited to 25

• Keywords should not be repeated, spiders avoid pages with repeated keywords

GOOGLE’S OTHER DATABASESGOOGLE’S OTHER DATABASES

What’s an SEO?What’s an SEO?• SEO = Search Engine Optimization

• Refers to the process of “optimizing” both the on-page and off-page ranking factors in order to achieve high search engine rankings for targeted search terms.

• Refers to the “industry” that revolves around obtaining high rankings in the search engines for desirable keyword search terms as a means of increasing the relevant traffic to a given website.

• Refers to an individual or company that optimizes websites for its clientele.

• Has a number of related meanings, and usually refers to an individual/firm that focuses on optimizing for “organic” search engine rankings

What Does a (good) SEO Do?What Does a (good) SEO Do?

• Researches desirable keywords and search phrases • Identifies search phrases to target (should be relevant to

business/market, obtainable and profitable)• “Cleans” and optimizes a website’s HTML code for

appropriate keyword density, title tag optimization, internal linking structure, headings and subheadings, etc.

• Helps in writing copy to appeal to both search engines and actual website visitors

• Studies competitors (competing websites) and search engines• Implements a quality link building campaign• Pushes for more content!• Monitors rankings for targeted search terms

Class AssignmentClass Assignment

1. Search a controversial topic in Google

2. Scan the first two pages of results

3. Visit one or two other sites

Evaluate their quality and reliability

• Try other search tools (Alta vista, yahoo, MSN, Ask.com)