I found this good article on another SEO blog via Twitter http://twitter.com/seodenver) - and thought it would be informative to our readers
A search engine is basically an information finding system in a computer that helps one find out information they are trying to find. They dramatically cut down the time needed to find the information one is looking for.
The concept of optimizing a website for the search engines began in the mid 1990s when webmasters saw the benefit on high ranking of their sites.
In earlier years webmasters were able to manipulate their websites with the result of them being able to get high ranking in the search engines regardless of whether the content of their web page was actually relevant to the targeted keyword or not.
Over time the search engine computations of the relevance of a particular web page to a particular keyword or set of keywords became more sophisticated so that the search engine could tell what web pages were relevant to a keyword being searched for and what web pages had just been manipulated just to gain traffic. This was done by those computing by being able to determine the quality and strength of incoming or inbound links to a web page. This system however was still not foolproof as webmasters were still able to manipulate by exchanging, buying or selling for the higher quality links to their sites. From that point on other factors were entered in to the computations the search engines use in ranking pages. This information is not available to webmasters and the public at large.
There are companies that are search engine optimisation companies. The service they sell to the public is to optimise their website to give it the best possibility of higher ranking with the search engines. If their techniques are too aggressive the effect may be detrimental to their clients to a point where their websites could be banned from search results. Not something you would want to pay someone for.
Some of the search engines have made efforts to communicate with the search engine optimisation companies to get their efforts aligned for everyones benefit. There are those who use search engine optimisation (SEO) to conform with the desires and wishes of the search engines and there are those who seek to get around the search engine rules and guidelines to get what traffic they can until they are caught.
It is a good practice to mix a campaign using search engine optimisation with one of a good paying campaign. The reason for this is that the computations that the search engines use do change and one may see a drop in unpaid traffic due to this factor. It is also a good practice to avoid search engine optimisation companies that make false promises they can not deliver, that guarantee a top rank with Google, that are secretive, that are nondescript about where your money goes, etc.