Original content is the key to better ranking. Search engines like good unique content and definitely rewards websites with such content by giving them a higher rank. However it is not an easy task to develop unique content as there are millions of sites and blogs on the Internet. And every SEO company is after unique content.

Search engines are not humans with eyes and brains but just an invention of human. Human is able to program them in such a way that they can judge the content on the page and check them for user friendliness. Even if anything looks fishy they have the power to penalize or ban that particular site.
 
All aspiring to be SEO content writing services providers should know the parameters to classify a unique content. Three major classifications of unique content are possible.
 
1. Editorial content: It is the content like articles and blogs written by humans. The best example for this is our blog (http://www.varologic.com/seo-news-articles-blog/). It can be written by anybody with the skill sets. If you think that you have the knowledge and the power to do such content then you can do it for yourself. Or you can hire SEO copywriters for this job. Different writers charge differently depending on the length of the article.
 
2. Machine-built content: This is something like auto generated content. Various content writing software products are available with special features. These generate original contents from RSS feeds like news, press releases and articles. Expedia and Bing travel use them for generating reviews or original data for a product or service. Zillo.com is an excellent example of a real estate site using content generator. Salary.com and Payscale.com are site in the human resource field using such a software.
 
3. User-generated content: You can get your site users to write content for you. It sounds a bit difficult but is extremely useful if rightly done. Once you have many followers you can put up a incentive based plan for those who will write content for you. Examples of such sites include Digg, YouTube and Wikipedia.

Towards the end decide your need of content and accordingly plan a strategy as to what kind of content you want. A combination of all three can also be used.