Well, its a term which is applied when we use SEO techniques that are illegal in the eyes of search engine.

Black hat SEO refers to the use of aggressive SEO tactics that do not follow search engines rules. For example, keyword stuffing and invisible text.

All those technique which do not follow SEO guideline that are black hat SEO. black hat SEO is totally risky for website, it can not make website traffic long time.

black hat seo is likely to affect your website if you do not manage it well

Black Hat seo techniques are more harmful from search engine keywords results

Black hat SEO is the illegal system which is used by out of rules.

leased line

Total Spam work is black hat SEO.

Black hat optimization includes short cut methods to optimization without implementing guidelines set by search engines.

Its an unethical Seo technique which doesnt follow google guidelines

Black Seo is to insert link avoiding google condition and try to create backlink.

Unethical SEO techniqes

Black hat SEO is the use of techniques that are not acceptable to search engines..black hat SEO techniques can get their sites penalized by or banned from search engines.

example of some main black hat technique are --

Keyword stuffing
Link farm
invisible text
doorway pages

Unethical way of doing SEO,google can punish your website

Black Hat is a SEO techniques that not follow google guidelines.

In search engine optimization (SEO) terminology, black hat SEO refers to the use of aggressive SEO strategies, techniques and tactics that focus only on search engines and not a human audience, and usually does not obey search engines guidelines.