Without traffic a website will struggle to fulfill its purpose while it is to inform entertain or sell products and services. Search engine optimization or SEO is important because when your site is optimized it is more likely to be found by Google, MSN and Yahoo. Also your site will be in turn visible by other search engines that get results from the largest three.
Now it is in the selection of which SEO or search engine optimization techniques that you use that makes the difference between white hat and black techniques. If you remember the western movies the one wearing the white hat was seen as a good guy and the one wearing the black hat was seen as a bad guy. In the world of SEO these terms have different meaning.
Although some people do take the moral view that the guy using the white hat SEO techniques is still the good guy. On the other hand that follow the back hat techniques would say that being black hat is about competitive with search engines while what hat is competing with your fellow webmasters.
In any case, white hat SEO are methods or techniques that fully comply with search engines guidelines. For example, writing an original article for your site would have considered a white hat SEO while using a software to generate thousands of content pages automatically would have been considered as a black hat. Of course, nothing is that simple in reality because there are several areas that would be considered as "gray".
Now admittedly, automatically generated black hat sites can sometimes generate short term profits, however, the search engines are getting smarter with their algorithms. When they discover using the black hat techniques that are generally de-index the pages of the site completely drying up the traffic for the website. Also this happens if the software used for automatically generated content leaves signs (known as footprints).
White hat SEO techniques focus on developing content that original and is useful to both the search engine spiders and to people. And the main draw back with white hat strategies are that they take longer to reach your desired goal but the result can be really significant when you do reach that goal! Much less chance that you get deindexed by search engines.
The point is if you want to build a long term business, do yourself a favor: keep everything white hat, above the board and do not worry about getting kicked out of the search engines. How about keeping profits month after month? Do it right from the start!