What is the difference between Black, white and grey hat technique? how they can effect a site and how they can be rectified?(with example)
I'd take a look at this article... goes into nice detail about the differences http://www.websitepublisher.net/article/white-gray-black/ Good luck to you
Currently black hat technology is not use. For optimizing white hat technology mostly use. More information check this website http://www.davechaffey.com/SEO-Best-Practice/What-is-black-hat-SEO http://searchsecurity.techtarget.com/sDefinition/0,,sid14_gci550815,00.html
Black hat- a.k.a search engine spamming..seo that pushes the boundaries of ethical practice. Uses to rank immediately Ex. cloaking, doorway pages and link-farms which are all a violation on the Google “Quality Guidelines†White Hat- contrast of Black Hat, it follows an ethical approach within the industry. Gray Hat where almost seo falls.. Its not a white nor a black hat(in between as what they say).. It follows some SEs guidelines but not all. Ex. duplicate content. It is remain ill-defined by all Google SEO guidelines.
nowadays black hat techniques are not worth the effort... SE's are more savvy than a few years ago. you'll do better with white hat (link exchange etc).