SEO is basically a process to develop the visibility of web pages on Search engines 

there many types and techniques are available to improve the rank of websites or Blogs

the basic type of seo are BLACK HAT SEO and WHITE HAT SEO 

the black hat seo is a scam and illegal its completely against of search engine Guidelines and policies 

while the White hat seo is a legal and proper way to develop the  rake of site get inspected amount of 

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