In my recent post about how to explain link-theory to a layman, I used the analogy of torchlights shining on your site to illustrate the importance of inbound links when it comes to making sure that Google can “see” what’s in your site when they’re looking to see if you’re relevant to a searcher’s query.

Of course, it isn’t just a matter of being seen.  You also want Google to know what your site’s pages are about and you need to convince them that your answer to the searcher’s question is more relevant than the millions of other websites that Google can see.

Shoemoney often advises people that the way to succeed in Google is to not make Google look stupid.  They want to provide searchers with the “right” answers to the queries they make.  Fooling Google’s algorithm into thinking that your site full of adverts and affiliate links is the best answer to a searcher’s query just so that you can pull in loads of traffic is a sure fire way of getting Matt Cutts to target your site for a smackdown.  Actually making a site that is the most relevant answer to a query might require more effort on your part, but it’s likely to provide better, more stable, results for you in the long run.

Bob Massa (the SEO-Guru) espouses the theory that Google’s algorithm operates not by raising “good” pages above the rest, but rather by lowering “not so good” or even “bad” pages further down the SERPs.  Essentially what this means is that Google doesn’t know how to tell what’s right, instead they work by finding the things that are “least wrong.”

So given that the objective of anyone with an interest in SEO is to gain higher placements in the SERPs, you’ve really got to ask yourself,

“Will It Float?”

(Or, because I’m British and as a nod to the David Letterman fans out there)…

“Is It Bouyant?”

You can divide the numerous signals that Google considers when ranking webpages into two main categories:

1. On-page SEO Factors
   These are the signals that Google looks for within the page itself and are entirely under your own control (or at least they should be).
2. Off-page SEO Factors
   These signals come from Google’s evaluation of external factors which are, to a greater or lesser extent, beyond your control (although with a bit of effort from a skilled SEO these can be managed to ensure your site is shown in a positive light).

These all add up to hundreds of individual factors that go into Google’s ranking algorithm and it would be way beyond the scope of a single post to try to detail all of them.  For that matter, no-one outside of the Googleplex knows for sure what all of the factors used by the algorithm actually are, but experience and examination by SEOs around the world has helped to highlight a number of the most important factors to consider when optimizing a website for search engine visibility.

On-page SEO Factors

• URL Factors
  There are plenty of factors that you need to take into account when designing your site’s URL structure.  Some of the most important ones are…
  
  Keywords in the URL - Either as part of your domain name, or within sub-directory or page titles.  If your URL matches the keywords used in a searcher’s query you have a much better chance of being seen as a highly relevant result for that search.

  Variables in dynamic URLs - For example, session IDs or product/post ID numbers, should be kept to a minimum.  Although Googlebot can crawl sites with dynamic URLs, there is a greater risk that it will get caught in a loop, re-crawling the same pages with different URLs over and over again (especially if your URLs contain multiple variables).

  Canonicalization - www.yourdomain.com can be treated by Google as a different page than yourdomain.com so it’s important to make sure that you have set up the necessary 301 redirection rules to ensure that either version will always resolve to your preferred URL.  It doesn’t matter whether you choose to favour the version with or without the www. but it is important to be consistent.  You can also use your Google Webmaster Tools account to tell Google which version you would prefer them to use.

• META Tag Information
  There are plenty of META Data Tags that you can add to your website’s pages, but the most important ones to consider from an SEO perspective are:

  TITLE - Technically not an actual META Tag (but this is as good a place to mention it as any), this is the line of text that appears at the top of your internet browser window and will be displayed by Google as the link to your page in their search results.  Keywords placed in Title Tags are given additional weight by Google’s algorithm when determining a page’s relevance for a given search query.  Note that only the first 65 characters of the Title will be displayed in the SERPs and that in addition to the SEO value of placing your target keywords in the Title, it is also your best opportunity to make a good first impression on searchers and entice them into visiting your site.

  DESCRIPTION - This is another place where it can be useful to include the keywords that your page is targetting.  Although it’s debatable just how much weight the Description Tag itself holds as far as search engine rankings are concerned, remember that search engines may well use your description tag as the snippet of text that they display for your page’s search result, so don’t just stuff it full of gobbledygook keywords.  Use it as anonther opportunity to write something that will entice searchers to click through to your page by convincing them that you have what they are searching for.

  KEYWORDS - The Keywords META Tag has largely been devalued in the ranking algorithms of modern search engines, because in the past it was abused by webmasters “stuffing” it full of irrelevant and repetitive terms.  Google, in particular, now ignores this information, but other search engines, like Yahoo, may still make some, limited, use of it when evaluating your page.  It’s unlikely to hurt you if you don’t bother to include a Keywords META Tag, but as long as you don’t go over the top and only include words that are actually relevant, it won’t hurt to put it in either.

• Header Tags
  The H1 to H6 Tags are another HTML element which can help you to emphasise important keywords within your webpage.  By using them to indicate headings for the various sections of your page’s Body Text, you are giving the search engines another way to figure out what is important about your page’s content.

• Body Text
  This is what should make up the bulk of your web page.  The most repeated phrase you’ll hear in SEO circles is, “Content is King!”  It’s something of a cliche, but the simple fact is that it’s true.  More specifically, TEXT CONTENT IS KING.  Search engines may be getting better at crawling Flash websites and they’re even developing the (very limited) ability to recognize images, but it’s going to be a long time before there is anything more important on your webpage than the actual words in your body text.  It’s easy to get caught up in metrics like “keyword density” when writing copy for your page, but the best advice I can give is just to write naturally.  Do your keyword research beforehand, decide what your subject is going to be and then forget about your keyword targets and just write about your subject.  You’ll find that doing this will automatically seed your keywords thoughout the piece without sounding forced and you’ll become a much better writer as a result.  You can also use bold text or italics to add further emphasis to specific words or phrases within your body text.  This may not do a great deal by itself, but in combination with the other on-page tactics mentioned here the cumulative effect can help to produce better results for your search engine rankings.  Once again, the important thing is to not over-do it, or you risk triggering one of the filters within the algorithm which could negatively affect your ranking.  Search Engine Optimization is definitely one field where too much of a good thing can be very bad for you.

• Site Architecture and Internal Linking Structure
  The layout of your website and its internal navigation is very important not just for your visitors to be able to find their way around and get to the pages containing the information they need and the goals that you have for them.  It’s also important for the search engine’s spiders to be able to crawl your site effectively, so that they can find and index your pages.  Make sure that you have standard HTML Text Links that the search engines can crawl in addition to any fancy Javascript dropdown menus (which might look nice but are basically invisible as far as Googlebot is concerned).

• Outbound Linking Profile
  Another measure of your site’s “worthiness” is taken by evaluating the kind of sites that you are linking to.  Google and the other earch engines may not look to kindly on your fluffy kittens in funny hats blog if the majority of sites in your blogroll are about the other kind of pussy.  Linking out to “bad neighbourhoods” is a surefire way of giving search engines the idea that you’re a “bad neighbour” as well.

Off-Page SEO Factors

In addition to the various on-page factors outlined above, the are also a wide range of factors external to your site which wil be considered by the search engines when determining your ranking for a searcher’s query.

• Inbound Linking Profile
  Google’s PageRank algorithm places an enormous amount of importance upon the number and type of links pointing to your site when evaluating your placement in the SERPs.  The more links you have pointing at your site, the more visible it will be to Google and by analyzing keywords in the anchor text used in links to your page search engines are able to gauge how relevant your page is for a particular query.  For example, your page about “Blue Gromits” could also rank well in searches for “Blue Widgets” if you have enough “Blue Widget” based links pointing to you.

• Domain History
  Search engines will also consider a variety of factors such as the age of you site’s domain and it’s behaviour in the past.  Having a well-established domain, that has been around for a long time and hasn’t previously been flagged for violating the search engines’ guidelines with spammy behaviour will increase your site’s “TrustRank” and help to raise you above newer or less well behaved sites.

• Competition
  One of the biggest external factors that you have the least control over is the amount of competition you face within your query space.  There may be thousands or even millions of other webpages out there that you will need to rise above in order to reach the top of the SERPs.  Conducting a thorough competitive analysis will not only help you to establish just how steep a hill you’ll have to climb, it will also allow you to know what your competitors are doing to rank so highly and give you the opportunity to out-do them.

• Search History and User Behaviour
  As Google and the other search engines move towards showing “Blended” or “Universal” search results for more queries they are likely to start placing greater emphasis on user behaviour, analyzing sequences of search queries in order to establish patterns for related searches or to predictively display more specific queries for a user.  Personalised search results are another area where previous searchers’ behaviour will provide an increasingly important signal for the search engines to determine a page’s ranking.  Although this is seen as having only a minor effect on search engine rankings at the moment, it’s likely that in the future Google will give greater weight to this metric by giving higher SERP placements to pages that have previously proven themselves to be useful to users with similar behavioural profiles.

This list is by no means exhaustive and there are hundreds of other factors that advanced SEO practioners will point to as having an effect on search engine placements.  What you see here are simply the primary factors that should be taken into account when trying to optimize a website for higher rankings.  Once these are taken care of you can move your focus into more complex areas to really push your rankings higher.