SEO Basics 
Introduction
SEO or Search Engine Optimisation is the practice of improving the quality of several variables within a website so that it is as relevant as possible to a search engine for a given topic.
The following article will explain some of the variables involved in this process.
Title Tag
The title tag is one of the most powerful tools available to optimise a site. The title of a page should be descriptive of the content on the page using the main targeted keywords. Limit the length of the title to 60 characters. Any longer than this could be a signal of spam to search engines.
Description Tag
The Description tag is often what will be displayed to a user after they have performed a search. A catchy and brief description will arouse a users' curiosity and draw them in to your site. The description tag should be descriptive of the content on the page.
Keywords Tag
The Keywords tag used to be very important. These days, the keywords tag has lost almost all of its importance due to past abuse by unethical site owners overstuffing the keywords tag blatantly. It is good practice to use the keywords tag but do not waste too much time or effort on it.
Header Tags
Header tags identify what the text below it will be about. There are several header tags, ranging from numbers 1 to 6, at a webmasters' disposal. Use Header tags but again do not abuse them. They should be descriptive and concise focusing on the main topic of the page or article.
Links
Links, links and more links. Building links to a site is probably the most important and time consuming activity a site owner can undertake. That said, relevant links from quality or authoritative sites are best. Avoid obtaining links from sites completely off topic or irrelevant to the nature of the site the optimisation is being performed on. Links to a site perform two actions. They increase traffic as a direct click through and increase Google Page Rank, thereby increasing your search results.
Obtaining links can be doe in a number of ways. Exchange or advertising purchase. Be careful purchasing links though, you may not always get what you bargained for. At the same time, buying links is frowned upon by search engines. Be careful!
Page Rank
More specifically, Google Page Rank. The higher the better. Page Rank is obtained from links pointing to a site. The higher Page Rank a link has, the better. Page Rank use to be a great way to improve search results. Again, because of abuse, its relevancy has been downgraded but it still plays an important roll in any SEO campaign.
Link Text
The text used in a link is a great indicator of the content on a page a link is pointing to. Use it, alternate the text and get more links.
Body Text
Write text for readers, not for search engines. That said, use your keyword phrases in your text. Use synonyms, repeat the words but most of all, write clearly, consisely and well.