Within search engine optimisation, white hat SEO is the generally accepted practice, where strong and relevant content, a strong and natural link profile and correct keywords are rewarded by the search engines. With black hat SEO, the opposite applies.
With this approach, you instead manipulate the search engine and thus also your ranking. It is not illegal to do, but it is unethical and cheating. It can also have consequences for you and your business if it is discovered. You risk Google removing some or all of your pages from their ranking, and this also applies to the pages you have optimised legally.
There is a lot of search engine optimisation that falls under this type of SEO, but some of the classic techniques that conflict with Google's guidelines are:
Duplicate content – where you copy the content from one page to another. Link manipulation – attempts to make your link building appear as natural as possible. Keyword stuffing – excessive use of keywords in content and meta tags with the aim of artificially boosting a page's ranking. Invisible content – text hidden behind an image, white text on a white background or similar. Cloaking – when you present website visitors with one result, while a search engine's crawlers are presented with something else.
Today, people also talk about grey hat SEO, which is a mixture of white hat and black hat respectively. This technique involves the use of some black hat techniques that are not as bad and are not penalised by Google to the same extent.
