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SEO Basics

Search Engine Optimization: a generic term for a set of techniques for improving the rankings of a website in an SERP (Search Engine Results Page).

SEO professionals advise clients on such matters as keyword analysis, site and content optimization, targeted audience behaviour, monitoring of site performance, and backlink generation.

Screenshot of an SERP
Screenshot of an SERP

Search Engine Goals

The stated goal of all search engines is to retain user loyalty through effective service. Primarily, this is achieved by returning a SERP list with a variety of best possible matches for a search query. This list will include a variety of types: text, images, video, etc.

There are ways to influence unduly the ranking of less relevant sites - a practice known as spamming. As a result, Google and the other search engines invest a great deal of effort in preventing spam results being presented with high rankings to searcher queries. Repeated attempts to unfairly gain rankings by site publishers may result in a downgrading of the site. Hence, it is the role of an SEO consultant to optimise rankings without compromising the legitimate relevance and authority of a site in the eyes of the search engine.

The Google Algorithm

Google utilises a sophisticated system for ranking sites for relevance, authority and other criteria, such as user responsiveness. A lot of data is collated and numerically evaluated to produce a rapid returns list (SERP) for the user to browse.

Search engines take into account two main categories of parameters: structure and content. Both of these involve analysing internal and external linking patterns.

Structure is concerned with the accessibility of information and the clarity of its presentation and thematic fidelity.

Content is assessed by means such as semantic analysis, which determines the relevance of material to the general theme of the page. For example, the presence of an advertisement on a topic totally unrelated to the theme of the page will downgrade that page's assessed relevance for specific keywords.

Sites which are active, and have the intention of informing a returning public, tend to grow organically. The indexes formulated by search engines will therefore also grow organically. Starting with a clear SEO blueprint for the information architecture will ensure these indexes develop and retain a profile which accurately matches the quality and utility of the site.

Paid responses and organic results

Those who have the budget may circumvent the algorithm vagaries by paying for rankings on the SERP. Google is a profit-making (and how!) private organisation, and makes its income primarily through advertising. One of the ways to advertise is to pay to appear at the top or in the right column of an SERP for specified search criteria. Important keywords need to be bid for. The more competitors there are in that particular field (e.g. 'budget hotels', 'cheap flights'), the more expensive it is to gain that pole position.

Organic results are those that are not paid. The investment to gain organic search results is not so much financial outlay as the time and effort necessary to create a site which gains the authority to return it with a high ranking for its realms of related query keywords.


When a user enters a search string, it is on average 2 or 4 words long. This reduces the link between the query and a targeted site to a limited number of keywords. Success at guiding meaningful traffic (traffic that wants and will use the found site) to a site depends on a clear identification and utilisation of these keywords and phrases.

It is not, however, sufficient to flood a site with content that contains many common keywords. The search engines are too clever for that. To obtain the authority which links certain queries to a suitable site requires painstaking development of structure and content which highlights for the search engine the true appropriateness of the site for the keyword in question.

It is not surprising then that a major area of interest in SEO involves keyword analytics. There are a number of tools provided for this purpose, and it becomes quickly apparent that SEO strategies depend greatly on the uniqueness of the site's offer to a highly competitive marketplace. If the obvious keywords are not likely to bring sufficient SERP ranking improvements, SEO moves into the area of the 'long tail'. These are search queries which are not directly related to a site's core subjects, but can be utilised to steer traffic to it. This is certainly a 'creative' area of research, and is probably where the term 'Art of SEO' originates.

Choice of URL and Age of Site

The URL is a major indicator to a search engine and human navigators about the nature of the site. Here enters also the question of geolocation. An organisation which operates principally locally can gain much more value from a country code TLD (top level domain), such as .ch or, than a universal TLD, such as .com and .net. Unless there is good reason to choose a generic international domain suffix, sites should not throw away the value of a local domain identity.

An older site, which has survived the vagaries of the online world for more than the average time, is more likely to be providing quality visitor experience. Spam (advertising and irrelevant content serving the publisher's purpose not the visitor's) on a site makes that site less likely to survive long, or gain the acceptance of its online community. It certainly will not be linked to and used as an authority by other sites. Long-lived sites are more likely to have found acceptance within their internet neighbourhood, and to have found a formula for developing in step with its needs. Search engines therefore automatically rank older sites higher than start-ups.

SEO practitioners need to take this into consideration. A client may think 'it is time for a fresh start' with a brash new domain name. If a domain has a pedigree (older than 5 years, say), that value is not to be discarded unless there is a good reason (and these exist).

Benefits of SEO

SEO is now a primary focus of web design. It meshes with the overall corporate strategy, and is already an integral part of mainstream marketing. There are three principal reasons for this:

  1. SEO provides large quantities of relevant and purposeful traffic to a site - traffic that is more likely to complete the goals of the site (direct sales or lead generation).
  2. High ranking in SERPs carries the implication (justly or not) that the site has quality, relevance and trustworthiness. A major league company should not allow itself to be pushed out of top rankings by smaller companies, if only for a question of prestige. SERP ranking is the new bricks and mortar of corporate identity.
  3. The reality of the new economy based on customer vertical search behaviour online means that traditional marketing is failing to provide new expectations. Organizations need to strive to lead in their sector's online environment, and cover areas of vertical search (video, news, social media) which they had previously disdained.

When should SEO be implemented?

Site optimization is not a single one-off project, but an iterative process. It is fundamental to all aspects of a site, and should be continuously revised as internal interaction with the site develops, and as the external ecosystem adapts to the site's growing dominance.

For best results, SEO would be the guiding basis for the site's structural design, as well as the content development. In this way, considerations such as ensuring backlinks will develop will be hardwired into the site. People do not respond favourably to something which they feel was not designed for them. Asking them to become involved as an evident afterthought will hinder the development of the kind of market interaction SEO thrives on.

Search Engines

Search engines have been a service provided by private companies since the inception of the World Wide Web in 1992. Their intent is to provide access to FTP sites via a central system which collates and organises the vast amounts of data involved in categorising and evaluating sites according to the criteria of relevance to a searcher's query.

The earliest web crawlers, such as Archie (Alan Emtage, 1990), relied on directories related to computer files in a specific computer network, and Gopher (Mark McCahill, 1991), used a hypertext paradigm to search for plain text references in files. By 1993, as the World Wide Web grew to many web servers, search engines like Mosaic (1993), and Wandex (Matthew Gray, 1993) improved the natural language keyword capabilities of search engines, and began to crawl the web to catalogue indexed pages on the web. Gradually, the content that was indexed extended to the full text on a web page.

With the need for a more effective search engine, many start-ups appeared between 1993 and 1998. These included: Excite (1993), Yahoo! (1994), WebCrawler (1994), Lycos (1994), Infoseek (1994), AltaVista (1995), Inktomi (1996), and AskJeeves (1997 - now Ask).


Today, the world's most popular search engine is Google. Google was a game-changer in the way search engines functioned. Previous search engines were unable to guarantee sufficiently well that a searcher's intent was being matched by the way sites were indexed. Words were not enough. The classic example is 'Jaguar'. The engines could not distinguish between the car make and the animal, or any other meaning a word or group of words might have. So both were presented, and it was up to the searcher to determine the relevancy of each site offered.

Google server hall
Google operates more than 1 million servers worldwide

In 1998, Larry Page and Sergey Brin launched their search engine, Google, which worked by a novel system of relevancy ranking. The initial system was unsophisticated: it merely counted the occurrence of search terms within a page. Soon they added a rough assessment of a website's ranking among the internet community based on the number of links from other sites (backlinks) to that site. This is the PageRank™ link analysis algorithm, which Google uses to assign numerical weighting to linked documents.

One of the restricting factors in the operation of search engines is energy consumption. Being predominantly American, their foremost consideration in this regard is cost, rather than environmental. The total global electrical power consumption of search engine servers is of the order of several gigawatt (GW), providing potentially thousands of petaflops of processing power.

Google alone would require more than a quarter of a nuclear power station to operate its servers (ref: MIT article: What it takes to power Google). All of the data centres of the world consume 1.3% of the world's electricity production.

Search Engine Usage

Search engine popularity varies world region by region. Here is an overview:


Global distribution puts Google way ahead (August 2014):

Crawling and Indexing

Search engines can return many hundreds of thousands of results for a query in a fraction of a second. How do they do it? Are these real results, or simply a statistical estimate? And what is the point, if users typically look at not only just the first page of search results (SERP 1), but only the first 3 or 4 of these results?! (When did anyone mention to you '... I was about to become disheartened, but then, at result number 512,325, I found just what I was looking for...'?)

The huge number of results is not the intention of the search engine, rather a consequence of, and insight into, how the search engine works when it crawls and indexes the World Wide Web.

The search engines utilise a programme called a 'spider', which makes its way through the web via a series of strands and nodes. The strands are pages on a domain, and the nodes are hyperlinks to other domains. If there are many return hyperlinks (AKA backlinks) to the first domain, the spider will find itself visiting that domain more often than a site stuck out on its own.


The spider collects data from its journey along the hyperlink highway, and ranks sites according to the perceived authority other sites grant them. The many elements which contribute to the complex and continuously-evolving algorithms used by search engines to rank pages are known as ranking factors or algorithmic ranking criteria. Google prefers the term signals.


The search engines attempt to assess the many millions of sites containing key word matches to the query in terms of relevance. This is done by assessing the intent of the query, and the number of matching occurrences of the keywords, as well as the context they appear in on a page.

If a key word appears as the page title, or in a heading tag (h1, h2 ...), that page is ranked higher.


Importance can also be thought of as popularity. The more references (hyperlinks) there are from other sites to a site, and the more authoritative those referring sites are perceived to be, the higher the importance ranking the search gives a site.

Greater authority is gained if the context of the referring site matches the content of the target site. A blog dedicated to SEO issues will have more importance than a site with, say, an ad unrelated to the general content of the page it appears on.

Search operators

Search engines offer a number of systems for refining search queries. These include:

  • [jacket shops -fur]
  • excludes the term 'fur' from search returns about 'jacket shops'. For obvious reasons, 'fur shops' are of no interest.

  • [shops +jacket]
  • the word 'jacket' must appear in the search query results. This can be used to specify the inclusion of words that may normally be excluded as unimportant, such as the definite article, the. It is also useful for disambiguation. Andrew Bone +Science -painter will ensure results about Andrew Bone the editor, and exclude results for the very fine painter by the same name.

  • ["science library"]
  • ensures the exact phrase 'science library' is searched for, a ¨somewhat smaller set than the billions of billions 'science' and 'library' individually would return

  • [quantum OR quanta]
  • pages which contain references to at least one of the two keywords

  • []
  • the search will be conducted only in the nominated domain

    [] : this will give an indication of the number of domains indexed by Google

    [site:info] : limits the search to the nominated TLD (top-level domain)

    [] : includes all sub-domains

  • [inurl:science]
  • ensures the word 'science' is in the url

    [allinurl:science library] : ensures both words appear in the url

  • [intitle:science]
  • ensures the word 'science' is in the page title

    [allintitle:science library] : ensures both words appear in the page title

  • [inanchor:science]
  • ensures the word 'science' is in the anchor text (the text used to refer to the page in a backlink)

    [allinanchor:science library] : ensures both words appear in the anchor text

  • [intext:Einstein]
  • ensures the word 'Einstein' is in the body text of a page

  • [ext:php] & [filetype:php]
  • either of these restricts the search to pages with the .php file extension

  • ["seo*compliance"]
  • will return any phrase which has 'seo' and 'compliance' with any word in between. e.g. 'seo design compliance' and 'seo structure compliance' are both returned

  • []
  • returns related pages. If a site links to the page, this query returns other sites linked to by that site

  • []
  • provides information about the page, such as the page title, description, related pages, and incoming links

  • []
  • shows the version of the page last time Google crawled it

    Content © Renewable.Media. All rights reserved. Created : September 1, 2014 Last updated :March 7, 2016

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Great Scientists

Edmond Becquerel

1820 - 1891

Alexandre-Edmond Becquerel is the second of four generations of notable Becquerel physicists. He continued his father's pioneering work in the field of electricity and luminescence. His son went on to win the Nobel Prize for Physics.

Edmond Becquerel, 1820 - 1891

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