Disclaimer* These are my personal views on Blackhat Search Engine Optimization Techniques. If you disagree please feel free to express yourself in the comment section bellow.
Blackhat SEO exploits weaknesses in the search engine algorithm by breaking rules and manipulating search results. Blackhat SEO is also about misrepresenting content to search engines through cloaking and other dirty techniques.
Blackhat SEO is mainly focused on fully automatic processes like comment spamming and they also take advantage of automatic directory submitters or they will slightly change/steal peoples content to submit to article directories with links to their own pages.
Blackhat SEO focuses on earning money without even trying to provide any value to the visitors! Often times you will see websites that are covered with affiliate advertisements and/or Adsence ads that will be listed high in the SERPs “Search Engine Results Pages” for keywords they are not related to in anyway.
Blackhat = Fast but short lived search engine love and Whitehat or Greyhat= A long-term process that will have great benefits over a longer stretch of time and the benefits will normally last for years as long as you never stop creating content, building links, and offering your visitors something to remember!
But not everything that Google says should be considered the law! There is a difference between flat out Blackhat manipulations and Greyhat SEO.