SEO Tutorial - Table of Contents

Keywords the Most Important Item in SEO >>

I.

Introduction – What Is SEO

Whenever you enter a query in a search engine and hit 'enter' you get a list of web results

that contain that query term. Users normally tend to visit websites that are at the top of this list as

they perceive those to be more relevant to the query. If you have ever wondered why some of these

websites rank better than the others then you must know that it is because of a powerful web marketing

technique called Search Engine Optimization (SEO).

SEO is a technique which helps search engines find and rank your site higher than the millions of other sites in

response to a search query. SEO thus helps you get traffic from search engines.

This SEO tutorial covers all the necessary information you need to know about Search Engine Optimization

- what is it, how does it work and differences in the ranking criteria of major search engines.

1. How Search

Engines Work

The first basic truth you need to know to learn SEO is that search

engines are not humans. While this might be obvious for everybody,

the differences between how humans and search engines view web pages

aren't. Unlike humans, search engines are text-driven. Although

technology advances rapidly, search engines are far from intelligent

creatures that can feel the beauty of a cool design or enjoy the

sounds and movement in movies. Instead, search engines crawl the Web,

looking at particular site items (mainly text) to get an idea what a

site is about. This brief explanation is not the most precise because

as we will see next, search engines perform several activities in

order to deliver search results – crawling, indexing,

processing, calculating relevancy, and retrieving.

First, search engines crawl the Web to see what is there.

This task is performed by a piece of software, called a crawler

or a spider (or Googlebot, as is the case with Google).

Spiders follow links from one page to another and index everything

they find on their way. Having in mind the number of pages on the Web

(over 20 billion), it is impossible for a spider to visit a site

daily just to see if a new page has appeared or if an existing page

has been modified, sometimes crawlers may not end up visiting your site for a

month or two.

What you can do is to check what a crawler sees from your site. As

already mentioned, crawlers are not humans and they do not see

images, Flash movies, JavaScript, frames, password-protected pages

and directories, so if you have tons of these on your site, you'd

better run the Spider Simulator below to see if these goodies are viewable by the spider. If

they are not viewable, they will not be spidered, not indexed, not

processed, etc. - in a word they will be non-existent for search

engines.

After a page is crawled, the next step is to index its

content. The indexed page is stored in a giant database, from where

it can later be retrieved. Essentially, the process of indexing is

identifying the words and expressions that best describe the page and

assigning the page to particular keywords. For a human it will not be

possible to process such amounts of information but generally search

engines deal just fine with this task. Sometimes they might not get

the meaning of a page right but if you help them by optimizing it, it

will be easier for them to classify your pages correctly and for you

– to get higher rankings.

When a search request comes, the search engine processes it

– i.e. it compares the search string in the search request with

the indexed pages in the database. Since it is likely that more than

one page (practically it is millions of pages) contains the search

string, the search engine starts calculating the relevancy of

each of the pages in its index with the search string.

There are various algorithms to calculate relevancy. Each of these

algorithms has different relative weights for common factors like

keyword density, links, or metatags. That is why different search

engines give different search results pages for the same search

string. What is more, it is a known fact that all major search

engines, like Yahoo!, Google, Bing, etc. periodically change their

algorithms and if you want to keep at the top, you also need to adapt

your pages to the latest changes. This is one reason (the other is

your competitors) to devote permanent efforts to SEO, if you'd like

to be at the top.

The last step in search engines' activity is retrieving the

results. Basically, it is nothing more than simply displaying them in

the browser – i.e. the endless pages of search results that are

sorted from the most relevant to the least relevant sites.

2. Differences Between the Major Search Engines

Although the basic principle of operation of all search engines is

the same, the minor differences between them lead to major changes in

results relevancy. For different search engines different factors are

important. There were times, when SEO experts joked that the

algorithms of Bing are intentionally made just the opposite of

those of Google. While this might have a grain of truth, it is a

matter a fact that the major search engines like different stuff and

if you plan to conquer more than one of them, you need to optimize

carefully.

There are many examples of the differences between search engines.

For instance, for Yahoo! and Bing, on-page keyword factors are of

primary importance, while for Google links are very, very important.

Also, for Google sites are like wine – the older, the better,

while Yahoo! generally has no expressed preference towards sites and

domains with tradition (i.e. older ones). Thus you might need more

time till your site gets mature to be admitted to the top in Google,

than in Yahoo!.

Keywords the Most Important Item in SEO >>