Keyword Density and Search Engine Optimization

«TITLE» tag

This is one of the most important tags for search engines. Make use of this fact in your seo work. Keywords must be used in the TITLE tag. The link to your site that is normally displayed in search results will contain text derived from the TITLE tag. It functions as a sort of virtual business card for your pages. Often, the TITLE tag text is the first information about your website that the user sees. This is why it should not only contain keywords, but also be informative and attractive. You want the searcher to be tempted to click on your listed link and navigate to your website. As a rule, 50-80 characters from the TITLE tag are displayed in search results and so you should limit the size of the title to this length.

Keywords in links
A simple SEO rule – use keywords in the text of page links that refer to other pages on your site and to any external Internet resources. Keywords in such links can slightly enhance page rank.

«ALT» attributes in images
Any page image has a special optional attribute known as "alternative text.” It is specified using the HTML «ALT» tag. This text will be displayed if the browser fails to download the image or if the browser image display is disabled. Search engines save the value of image ALT attributes when they parse (index) pages, but do not use it to rank search results.

Currently, the Google search engine takes into account text in the ALT attributes of those images that are links to other pages. The ALT attributes of other images are ignored. There is no information regarding other search engines, but we can assume that the situation is similar. We consider that keywords can and should be used in ALT attributes, but this practice is not vital for seo purposes.

Keyword Density and SEO

Keyword page density is a measure of the relative frequency of the word in the text expressed as a percentage. For example, if a specific word is used 5 times on a page containing 100 words, the keyword density is 5%. If the density of a keyword is too low, the search engine will not pay much attention to it. If the density is too high, the search engine may activate its spam filter. If this happens, the page will be penalized and its position in search listings will be deliberately lowered.

The optimum value for keyword density is 5-7%. In the case of keyword phrases, you should calculate the total density of each of the individual keywords comprising the phrases to make sure it is within the specified limits. In practice, a keyword density of more than 7-8% does not seem to have any negative seo consequences. However, it is not necessary and can reduce the legibility of the content from a user’s viewpoint. 

Location of keywords on a page

A very short rule for SEO experts – the closer a keyword or keyword phrase is to the beginning of a document, the more significant it becomes for the search engine. 

Text format and SEO

Search engines pay special attention to page text that is highlighted or given special formatting. We recommend:

- use keywords in headings. Headings are text highlighted with the «H» HTML tags. The «h1» and «h2» tags are most effective. Currently, the use of CSS allows you to redefine the appearance of text highlighted with these tags. This means that «H» tags are used less than nowadays, but are still very important in seo work.;

- Highlight keywords with bold fonts. Do not highlight the entire text! Just highlight each keyword two or three times on the page. Use the «strong» tag for highlighting instead of the more traditional «B» bold tag.

Internal ranking factors

Several factors influence the position of a site in the search results. They can be divided into external and internal ranking factors. Internal ranking factors are those that are controlled by seo aware website owners (text, layout, etc.) and will be described next. 

Web page layout factors relevant to seo

Amount of text on a page

A page consisting of just a few sentences is less likely to get to the top of a search engine list. Search engines favor sites that have a high information content. Generally, you should try to increase the text content of your site in the interest of seo. The optimum page size is 500-3000 words (or 2000 to 20,000 characters). 

Search engine visibility is increased as the amount of page text increases due to the increased likelihood of occasional and accidental search queries causing it to be listed. This factor sometimes results in a large number of visitors.

Number of keywords on a page

Keywords must be used at least three to four times in the page text. The upper limit depends on the overall page size – the larger the page, the more keyword repetitions can be made. Keyword phrases (word combinations consisting of several keywords) are worth a separate mention. The best seo results are observed when a keyword phrase is used several times in the text with all keywords in the phrase arranged in exactly the same order. In addition, all of the words from the phrase should be used separately several times in the remaining text. There should also be some difference (dispersion) in the number of entries for each of these repeated words. 

Let us take an example. Suppose we optimize a page for the phrase "seo software” (one of our seo keywords for this site) It would be good to use the phrase “seo software” in the text 10 times, the word “seo” 7 times elsewhere in the text and the word “software” 5 times. The numbers here are for illustration only, but they show the general seo idea quite well.

Common search engine principles

To understand seo you need to be aware of the architecture of search engines. They all contain the following main components:

Spider - a browser-like program that downloads web pages.

Crawler – a program that automatically follows all of the links on each web page.

Indexer - a program that analyzes web pages downloaded by the spider and the crawler. 

Database– storage for downloaded and processed pages.

Results engine – extracts search results from the database. 

Web server – a server that is responsible for interaction between the user and other search engine components. 

Specific implementations of search mechanisms may differ. For example, the Spider+Crawler+Indexer component group might be implemented as a single program that downloads web pages, analyzes them and then uses their links to find new resources. However, the components listed are inherent to all search engines and the seo principles are the same. 

Spider. This program downloads web pages just like a web browser. The difference is that a browser displays the information presented on each page (text, graphics, etc.) while a spider does not have any visual components and works directly with the underlying HTML code of the page. You may already know that there is an option in standard web browsers to view source HTML code. 

Crawler. This program finds all links on each page. Its task is to determine where the spider should go either by evaluating the links or according to a predefined list of addresses. The crawler follows these links and tries to find documents not already known to the search engine. 

Indexer. This component parses each page and analyzes the various elements, such as text, headers, structural or stylistic features, special HTML tags, etc.

Database. This is the storage area for the data that the search engine downloads and analyzes. Sometimes it is called the index of the search engine.

Results Engine. The results engine ranks pages. It determines which pages best match a user's query and in what order the pages should be listed. This is done according to the ranking algorithms of the search engine. It follows that page rank is a valuable and interesting property and any seo specialist is most interested in it when trying to improve his site search results. In this article, we will discuss the seo factors that influence page rank in some detail. 

Web server. The search engine web server usually contains a HTML page with an input field where the user can specify the search query he or she is interested in. The web server is also responsible for displaying search results to the user in the form of an HTML page. 

History of Search Engines

In the early days of Internet development, its users were a privileged minority and the amount of available information was relatively small. Access was mainly restricted to employees of various universities and laboratories who used it to access scientific information. In those days, the problem of finding information on the Internet was not nearly as critical as it is now.

Site directories were one of the first methods used to facilitate access to information resources on the network. Links to these resources were grouped by topic. Yahoo was the first project of this kind opened in April 1994. As the number of sites in the Yahoo directory inexorably increased, the developers of Yahoo made the directory searchable. Of course, it was not a search engine in its true form because searching was limited to those resources who’s listings were put into the directory. It did not actively seek out resources and the concept of seo was yet to arrive.

Such link directories have been used extensively in the past, but nowadays they have lost much of their popularity. The reason is simple – even modern directories with lots of resources only provide information on a tiny fraction of the Internet. For example, the largest directory on the network is currently DMOZ (or Open Directory Project). It contains information on about five million resources. Compare this with the Google search engine database containing more than eight billion documents.

The WebCrawler project started in 1994 and was the first full-featured search engine. The Lycos and AltaVista search engines appeared in 1995 and for many years Alta Vista was the major player in this field.

In 1997 Sergey Brin and Larry Page created Google as a research project at Stanford University. Google is now the most popular search engine in the world.

Currently, there are three leading international search engines – Google, Yahoo and MSN Search. They each have their own databases and search algorithms. Many other search engines use results originating from these three major search engines and the same seo expertise can be applied to all of them. For example, the AOL search engine (search.aol.com) uses the Google database while AltaVista, Lycos and AllTheWeb all use the Yahoo database.

Introduction to SEO

This document is intended for webmasters and site owners who want to investigate the issues of SEO ( Sarch Engine Optimization ) and promotion of their resources. It is mainly aimed at beginners, although I hope that experienced webmasters will also find something new and interesting here. There are many articles on seo on the Internet and this text is an attempt to gather some of this information into a single consistent document.

   Information presented in this text can be divided into several parts:

   - Clear-cut seo recommendations, practical guidelines.

   - Theoretical information that we think any seo specialist should know.

   - Seo tips, observations, recommendations from experience, other seo sources, etc.

How Search Works

Doorway page

Doorway pages are web pages that are created for Spamdexing, this is, for spamming the index of a search engine by inserting results for particular phrases with the purpose of sending visitors to a different page. They are also known as bridge pages, portal pages, jump pages, gateway pages, entry pages and by other names. Doorway pages that redirect visitors without their knowledge use some form of cloaking.

What Is The Google Dance?

Whenever we are at trade shows, run seminars, or speak at symposiums we get asked the question "what is the Google dance?" We've heard a few different things referred to as "the Google Dance", but only one is really correct. It's the period when Google is rebuilding its rankings, and results fluctuate widely for a 3 to 5 day period.

How Often Does The Google Dance Happen?
The name "Google Dance" was in the past used to describe the period that a major index update of the Google search engine are being implemented. These major Google index update occured on average every 36 days or 10 times per year. It was easiest be identified by significant changes in search results, and by an updating of Google's cache of all indexed pages. These changes would be evident from one minute to the next. But the update did not proceed as a switch from one index to another like the flip of a switch. In fact, it took several days to finish the complete update of the index.

Because Google, like every other search engine, depends on their customers knowing that they deliver authoritative reliable results 24 hours of the day, seven days a week, updates pose a serious issue. They can not shut down for maintenance and they cannot afford to go offline for even one minute. Hence, we had the Dance. Every search engine goes through it, some more or less often than Google. However, it is only because of Google's reach that we pay attention to its rebuild more than that of any other engine.

Since August 2003, the famous / infamous Google Dance is no more. Or rather it has become less dramatic. Google now performs updates every week, with most movement occurring on Mondays. These ongoing updates feature mostly minor algorithm and index updates.

So, during any month there will be minor changes in rankings. This is because Google's bot or spider is always running and finding new material. It also happens because the bot may have detected that a website no longer exists, and needs to be deleted from the index. During the Dance, the Googlebot will revisit every website, figure out how many sites link to it, and how many it links out to, and how valuable these links are.

Because Google is constantly crawling and updated selected pages, their search results will vary slightly over the course of the month. However, it is only during the Google Dance that these results can swing wildly. You also need to consider that Google has multiple data centers, sharing more than 10,000 servers. Somehow, the updates to the index that occur during the month, and outside of the Google Dance have to get transferred throughout. It's a constant process for Google, and every other search engine. These ongoing, incremental updates only affect parts of the index at any one time.

Checking The Google Dance

Until January 2004, Google had 12 main www servers online, which were as follows:

    * www-ex.google.com - (where you get when you type www.google.com)
    * www-sj.google.com - (which can also be accessed at www2.google.com)
    * www-va.google.com - (which can also be accessed at www3.google.com)
    * www-dc.google.com
    * www-ab.google.com
    * www-in.google.com
    * www-zu.google.com
    * www-cw.google.com
    * www-fi.google.com - found in May 2003.
    * www-gv.google.com - found in August 2003.
    * www-gv2.google.com - found in September 2003.
    * www-kr.google.com - found in October 2003.

At some point in January, these servers stopped accepting connections, and the only servers easy to connect to were:

    * www.google.com
    * www2.google.com
    * www3.google.com

As well as the numeric address databases - which people keep discovering, and kindly help us keep abreast of.

    * 216.239.37.99
    * 216.239.39.99
    * 216.239.41.99
    * 216.239.51.99
    * 216.239.37.104
    * 216.239.41.104
    * 216.239.37.147
    * 64.233.161.98
    * 64.233.161.99
    * 64.233.161.104
    * 64.233.161.105

At any time during an index update you can check the Google servers, and they will display sometime wildly differing results, thus they are said to be "dancing", and hence the name "Google Dance".

In the past, the easiest way to check if the Google Dance was happening was to go to www.google.com, and do a search. Look at the blue bar at the top of the page. It would have the words "Results 1 - 10 of about 626,000. Search took 0.48 seconds" Then check the same search on www2.google.com, and www3.google.com. If you were seeing a different number of total pages for the same search, then the Google Dance was on. You could also check all the variations above. www2 is really www-sj, and www3 is www-va. We have found that all the others need their full www-extension.google.com in the url if you want to test them properly. Once the numbers, and the order of results on all 10 www's are the same, you knew the dance is over.

Importance Of The Google Dance

For most people, this event in and of itself was not important. However for anyone in the search engine optimization industry it was a period of note. Pages got temporarily dropped. Sometimes it lasted a day. People panicked. Then they are re-added, and they are better placed than before, and things calmed down. It's interesting to see how overpoweringly important this one engine is. For more information on about this search engine, or any other, please read our sections on The Search Engines.

About Google Instant

Google Instant is a new search enhancement that shows results as you type. We are pushing the limits of our technology and infrastructure to help you get better search results, faster. Our key technical insight was that people type slowly, but read quickly, typically taking 300 milliseconds between keystrokes, but only 30 milliseconds (a tenth of the time!) to glance at another part of the page. This means that you can scan a results page while you type.

The most obvious change is that you get to the right content much faster than before because you don’t have to finish typing your full search term, or even press “search.” Another shift is that seeing results as you type helps you formulate a better search term by providing instant feedback. You can now adapt your search on the fly until the results match exactly what you want. In time, we may wonder how search ever worked in any other way.

Benefits

Faster Searches: By predicting your search and showing results before you finish typing, Google Instant can save 2-5 seconds per search.

Smarter Predictions: Even when you don’t know exactly what you’re looking for, predictions help guide your search. The top prediction is shown in grey text directly in the search box, so you can stop typing as soon as you see what you need.

Instant Results: Start typing and results appear right before your eyes. Until now, you had to type a full search term, hit return, and hope for the right results. Now results appear instantly as you type, helping you see where you’re headed, every step of the way.