Working of Crawler based Search Engines

Search for anything using your favorite crawler-based search engine. Nearly instantly, the search engine will sort through the millions of pages it knows about and present you with ones that match your topic. The matches will even be ranked, so that the most relevant ones come first. Of course, the search engines don't always get it right. Non-relevant pages make it through, and sometimes it may take a little more digging to find what you are looking for. But, by and large, search engines do an amazing job.

Unfortunately, search engines don't have the ability to ask a few questions to focus your search. They also can't rely on judgment and past experience to rank web pages, in the way humans can.

So, how do crawler-based search engines go about determining relevancy, when confronted with hundreds of millions of web pages to sort through? They follow a set of rules, known as an algorithm. Exactly how a particular search engine's algorithm works is a closely-kept trade secret. However, all major search engines follow the general rules below.

Location, Location, Location...and Frequency
One of the the main rules in a ranking algorithm involves the location and frequency of keywords on a web page. Call it the location/frequency method, for short.Pages with the search terms appearing in the HTML title tag are often assumed to be more relevant than others to the topic.Search engines will also check to see if the search keywords appear near the top of a web page, such as in the headline or in the first few paragraphs of text. They assume that any page relevant to the topic will mention those words right from the beginning.

Frequency is the other major factor in how search engines determine relevancy. A search engine will analyze how often keywords appear in relation to other words in a web page. Those with a higher frequency are often deemed more relevant than other web pages.

Spice in the Recipe
Now it's time to qualify the location/frequency method described above. All the major search engines follow it to some degree, in the same way cooks may follow a standard chili recipe. But cooks like to add their own secret ingredients. In the same way, search engines add spice to the location/frequency method. Nobody does it exactly the same, which is one reason why the same search on different search engines produces different results.
To begin with, some search engines index more web pages than others. Some search engines also index web pages more often than others. The result is that no search engine has the exact same collection of web pages to search through. That naturally produces differences, when comparing their results.
Search engines may also penalize pages or exclude them from the index, if they detect search engine "spamming." An example is when a word is repeated hundreds of times on a page, to increase the frequency and propel the page higher in the listings. Search engines watch for common spamming methods in a variety of ways, including following up on complaints from their users.

Off The Page Factors
Crawler-based search engines have plenty of experience now with webmasters who constantly rewrite their web pages in an attempt to gain better rankings. Some sophisticated webmasters may even go to great lengths to "reverse engineer" the location/frequency systems used by a particular search engine. Because of this, all major search engines now also make use of "off the page" ranking criteria.
Off the page factors are those that a webmasters cannot easily influence. Chief among these is link analysis. By analyzing how pages link to each other, a search engine can both determine what a page is about and whether that page is deemed to be "important" and thus deserving of a ranking boost. In addition, sophisticated techniques are used to screen out attempts by webmasters to build "artificial" links designed to boost their rankings.

Another off the page factor is click through measurement. In short, this means that a search engine may watch what results someone selects for a particular search, then eventually drop high-ranking pages that aren't attracting clicks, while promoting lower-ranking pages that do pull in visitors. As with link analysis, systems are used to compensate for artificial links generated by eager webmasters.

Comments and Queries are welcomed!

Working method of Search Engines- General

The term "search engine" is often used generically to describe both crawler-based search engines and human-powered directories. These two types of search engines gather their listings in radically different ways.

Crawler-Based Search Engines
Crawler-based search engines, such as Google, create their listings automatically. They "crawl" or "spider" the web, then people search through what they have found. If you change your web pages, crawler-based search engines eventually find these changes, and that can affect how you are listed. Page titles, body copy and other elements all play a role.

Human-Powered Directories
A human-powered directory, such as the Open Directory, depends on humans for its listings. You submit a short description to the directory for your entire site, or editors write one for sites they review. A search looks for matches only in the descriptions submitted.
Changing your web pages has no effect on your listing. Things that are useful for improving a listing with a search engine have nothing to do with improving a listing in a directory. The only exception is that a good site, with good content, might be more likely to get reviewed for free than a poor site.


The Parts Of A Crawler-Based Search Engine
Crawler-based search engines have three major elements. First is the spider, also called the crawler. The spider visits a web page, reads it, and then follows links to other pages within the site. This is what it means when someone refers to a site being "spidered" or "crawled." The spider returns to the site on a regular basis, such as every month or two, to look for changes.

Everything the spider finds goes into the second part of the search engine, the index. The index, sometimes called the catalog, is like a giant book containing a copy of every web page that the spider finds. If a web page changes, then this book is updated with new information.Sometimes it can take a while for new pages or changes that the spider finds to be added to the index. Thus, a web page may have been "spidered" but not yet "indexed." Until it is indexed -- added to the index -- it is not available to those searching with the search engine. It may therefore happen that you could not find your site on search engine for the relevant keywords even though you have submitted it to search engine.

Search engine software is the third part of a search engine. This is the program that sifts through the millions of pages recorded in the index to find matches to a search and rank them in order of what it believes is most relevant.

Major Search Engines: The Same, But Different
All crawler-based search engines have the basic parts described above, but there are differences in how these parts are tuned. That is why the same search on different search engines often produces different results. Information on this page has been drawn from the help pages of each search engine, along with knowledge gained from articles, reviews, books, independent research, tips from others and additional information received directly from the various search engines.

Check out the next post for more information on the working technique of Crawler based search engines.

Over-Optimization in SEO

Every website need to be in top rankings on all the major search engines and to achieve high rankings SEO experts use various SEO techniques, mostly ethical or sometimes unethical. Using unethical SEO practices sometimes results in temporarily or permanently exclusion of websites from the index of major search engines like Google for using so called 'black hat' SEO techniques. The reaction of search engines is easy to understand with many unethical tricks and cheats that SEO experts use in their website optmization strategy, the relevancy of results is compromised to the point where search engines initiate to give completely irrelevant and manipulated search results. Or if search engines do not catch you red handed right away, your competitors might report you for your misdoings.

Keyword Density/Keyword Stuffing -
SEO experts try to push their websites to top positions through many ways that might results in questionable practices, like keyword stuffing which is considered an unethical practice because what you actually do is use the keyword in question throughout the text suspiciously often. Having in mind that the recommended keyword density is from 3 to 7%, anything above this, say 10% density starts to look very much like keyword stuffing and it is likely that will not get unnoticed by search engines. A text with 10% keyword density can hardly make sense, if read by a human. Some time ago Google implemented the so called “Florida Update” and essentially imposed a penalty for pages that are keyword-stuffed and over-optimized in general.

Generally, keyword density in the title, the headings, and the first paragraphs matters more. Needless to say that you should be especially careful not to stuff these areas. Try the Keyword Density Cloud tool to check if your keyword density is in the acceptable limits, especially in the above-mentioned places. If you have a high density percentage for a frequently used keyword, then consider replacing some of the occurrences of the keyword with synonyms. Also, generally words that are in bold and/or italic are considered important by search engines but if any occurrence of the target keywords is in bold and italic, this also looks unnatural and in the best case it will not push your page up.

Duplicate Content -
SEO has a basic rule that content is always the king. But it should be unique & relevant. In terms of Google, duplicate content means text that is the same as the text on a different page on the SAME site or on a sister-site, or on a site that is heavily linked to the site in question and it can be presumed that the two sites are related; i.e. when you copy and paste the same paragraphs from one page on your site to another, then you might expect to see your site's rank drop. Most SEO experts believe that syndicated content is not treated as duplicate content and there are many examples of this. If syndicated content were duplicate content, that the sites of news agencies would have been the first to drop out of search results. Still, it does not hurt to check from time if your site has duplicate content with another, at least because somebody might be illegally copying your content and you do not know. The Similar Page Checker tool will help you see if you have grounds to worry about duplicate content.

Doorway Pages and Hidden Text -
Another common keyword scam is doorway pages. Before Google introduced the PageRank algorithm, doorways were a common practice and there were times when they were not considered an illegal optimization. A doorway page is a page that is made especially for the search engines and that has no meaning for humans but is used to get high positions in search engines and to trick users to come to the site. Although keywords are still very important, today keywords alone have less effect in determining the position of a site in search results, so doorway pages do not get so much traffic to a site but if you use them, don't ask why Google punished you.
Like doorway pages is a scam called hidden text. This is text, which is invisible to humans e.g. the text color is the same as the page background but is included in the HTML source of the page, trying to fool search engines that the particular page is keyword-rich. Needless to say, both doorway pages and hidden text can hardly be qualified as optimization techniques, there are more manipulation than everything else.

Links Spam -
Links are another major SEO tool and like the other SEO tools it can be used or misused. While backlinks are certainly important, for Yahoo backlinks are important as quantity, while for Google it is more important what sites backlinks come from, getting tons of backlinks from a link farm or a blacklisted site is begging to be penalized. Also, if outbound links (links from your site to other sites) considerably outnumber your inbound links (links from other sites to your site), then you have put too much effort in creating useless links because this will not improve your ranking. You can use the Domain Stats Tool to see the number of backlinks (inbound links) to your site and the Site Link Analyzer to see how many outbound links you have.

Using keywords in links (the anchor text), domain names, folder and file names does boost your search engine rankings but again, the precise measure is the boundary between topping the search results and being kicked out of them. For instance, if you are optimizing for the keyword “cat”, which is a frequently chosen keyword and as with all popular keywords and phrases, competition is fierce, you might not see other alternative for reaching the top but getting a domain name like http://www.cat-cats-kittens-kitty.com, which no doubt is packed with keywords to the maximum but is first – difficult to remember, and second – if the contents does not correspond to the plenitude of cats in the domain name, you will never top the search
results.

Although file and folder names are less important than domain names, now and then you can include “cat” (and synonyms) in them and in the anchor text of the links। This counts well, provided that anchors are not artificially stuffed (for instance if you use “cat_cats_kitten” as anchor for internal site links this anchor certainly is stuffed). While you have no control over third sides that link to you and use anchors that you don't like, it is up to you to perform periodic checks what anchors do other sites use to link to you. A handy tool for this task is the Backlink Anchor Text Analysis, where you enter the URL and get a listing of the sites that link to you and the anchor text they use.

Finally to conclude, Google and the other search engines makes no difference if a site is intentionally over-optimized to cheat them or over-optimization is the result of good intentions, so no matter what your motives are, always try to keep to reasonable SEO practices and follow the search engine guidelines.

Importance of Search Engine Optimization

Why is Search Engine Optimization Important?

Internet has provided useful and innovative ways to revolutionize our daily life by crawling into different dimensions of lives - business, communication, information dissemination, personal relationships. People have made a paradigm shift towards using the Internet to aid them in their daily activities.

People are continuously struggling to get noticed in the world of the Internet. Websites are growing like mushrooms everywhere, every time. How can one's website get past the millions of other websites and eventually be noticed by its target audience?

Search engine optimization aims to achieve the goal of getting more visitors to a website by helping it get higher rankings in the search engines. This simply means that search engine optimization's goal is to make a website appear on the first pages, if not the first page of a search done through the search engine.

There are two ways to be able to get noticed by search engines. One is through pay-per-click-advertisements. A good example of a pay-per-click system that is employed by search engines is the Google Adwords system. It has created a hype and has given Google around 5 billion dollars in terms of revenue per year. Webmasters can place their bids to be shown when a keyword is searched by a surfer. The highest bidders will get their sites to appear first when the search is being done.

The second way of GETTING high rankings from search engines is through organic searches. Search engines evaluate websites by using what they call "spiders." These programs scan the websites and collects information about them. They then collate the information and pass it on to the search engine. This area is primarily the main arena of search engine optimization. It utilizes a set of methods to be able to get search engines to list the website on high ranks.

Traffic
The main purpose of search engine optimization is to increase the traffic generated by a website. Websites are built to be seen by Internet surfers and search engines can help it achieve this goal. The power of the search engine should not be underestimated. It is one of the building blocks of the foundation of the Internet. A survey showed that 90% of all Internet users employ search engines to aid them in their Internet-related activities. Google, the dominant player in the search engine industry, generates 70% of all search-related Internet activity.

People and Search Engines are alike
Search engines behave like people. They like websites which contain substantive information about a certain topic. The best sites usually appear first in search engines because people like them as well as the search engines.

Search engine optimization does not only generate traffic, it helps maintain the traffic. The behavior of the search engine is indicative to the behavior of the people who visit the website. Search engine optimization leads to the optimization of a webpage or a website. It will lead to a website which is more organized and a website which contains substantive information.

The use of the Search Engine to be able to target one's target audience is one of the most effective Internet marketing strategies. It is not like other on-line marketing techniques (such as email marketing) which can lead to a lot of leakages in terms of targeting the right audience.

Search engines segment the market and connect the right people together. People search for topics which they are interested in and this is the main strength of search engines in connecting markets together.

Cost Effectiveness
One can do search engine optimization under the ASSUMPTION that he knows what he is doing. Search engine optimization is a full-time job and has a very long learning curve. This is why most people would resort to out-sourcing the job to experts who are good at what they do. One should be cautious, however, in hiring a search engine optimization company or consultant. Factors such as pricing and service should carefully be assessed before signing a deal. If done properly, search engine optimization is a very cost effective way of getting more people to know about one's products or to know about a certain issue or event that a website is disseminating.

SEO is very important for websites since it determines the position of the website in comparison with its competitors. It does not only generate traffic from the targeted audience but is also a cost-effective way of optimizing the website.