One of the keys to becoming more successful in anything is to understand that you don't know everything about that subject. There is always more to learn, and that is becoming more and more apparent as I have been plunged full force into the witchcraft known as SEO. Not to say that I am totally green on the subject, but it's always interesting to find out the pieces here and there that you have been missing through the years.
With that in mind I thought I should go ahead and throw together a quick crash course in some basic principles of SEO, some of which I knew already and some of which I had no idea. Even though I was beaten to the punch while I was drafting this, I figured I would spew forth my knowledge of the subject as well.
One quick note before I do get into the basics, keep in mind that the art of SEO can and is in a lot of occasions a full time job. Some of these tips are things that you can implement easily as you develop your sites and will raise your page rank, and thus your visibility on the search engines. There are a lot of other techniques and things to monitor, and a lot more then I care to cover here quite honestly.
Title, Keywords, and Description
These are the obvious ones that pretty much everyone knows about. If you ask just about anyone in the field of design you will get this answer straight away. What you might not know though is that there are some rules surrounding each of these elements. How they should be structured, what they should contain as well and how long they should be.
Obviously they should be unique, descriptive, and concise. Along with that the title tag shouldn't be anymore then70 characters whereas the description should be limited to no more then 155 characters.
Heading Tags
The heading tags are a very important aspect to your pages markup. They strengthen the information contained in the title, and provide a logical table of contents about the information on the page. These tags are weighted heavier than most of the tags on the page with the exception of the title.
Generally the <h1> tag is always the pages title. Often times I also like to insert the <h2> above the <h1> tag and include the pages parent if there is one. Doing this helps make the association about he hierarchy of your site structure.
Bold/Strong Tags
This is one that I certainly admit I didn't know about. Bold and Strong tags are also weighted more heavily then regular content on the page, so use with care.
Page/Content Length
Recently we had a series of location pages that we were working on, and while we were looking into how these came up using our internal search engine we found that one of the smaller off site campus pages was ranked higher then the main campus of the Hospital. Once we had looked into it further we found that this was because the smaller location page contained more specific information on how to get patients to the location since it was harder to find and less known. In other words the content was much more developed and the search engine awarded that.
This is just one example, but the pages content and length play a large role in how the site is indexed, and how those pages are ranked.
URL Parameters
URL parameters are typically associated with database applications. There are really two ways that these can be implemented.
One method is called a querystring parameter, where often times the pages name is trailed by a question mark, some sort of identifier, followed by and equals sign and the variable. Something like this: default.aspx?id=40
Lately, especially when Ruby on Rails was released, fancy URL's became popular. These are very similar to querystring parameters except a little more user friendly. Instead of calling a specific database item by id, it instead uses what looks like a folder structure, and might look something like this: http://www.designsbyjohnson.com/posts/principles_of_seo/
When using either of these methods there is a rule to keep in mind. When using a querystring it is advised that you don't use anymore then two parameters in your URL. If you are are using the fancy URL method, the depth of your URL should never exceed two layers deep.
Typically speaking these two options aren't as important as the others as this deals primarily with Web applications. Many times applications are not index by search engines other then their own internal engines, and so this becomes a less important point.
These are all simple guidelines and principles of SEO to help your pages get a higher ranking when it comes to search engines. None of these are guaranteed, however they will certainly not hurt. So good luck with your SEO magic!