* Unrelated Keywords * Keyword Stuffing * Cloaking * Gateway Pages * Hidden Text * Cookie Stuffing * URL Hijacking * Referrer Spam * Spam Ping * Blog Spam * Duplicate Content
Also- Mispsellings Scraping Ad only pages Fake news Link farm Hidden affiliate links Those are black hat techniques too, that need to avoid.
Honestly, you should avoid anything that might be perceived as 'blackhat' SEO. Anything they talk about on BlackHatWorld.com -- you should avoid. Google has an excellent track record of of identifying these blackhat tactics and heavily penalizing them.
Google Work Day by day to Make google as the Best Search Engine and did't Give the chance to their competitor to Grow Up. In that case if you use Black hate SEO then you should Heavily Penalize by Google.
Blackhat techniques does not follow the rules and regulations of Google guidelines, Google will penalize these websites.
Purchasing garbage banklinks, as someone already said here, but from personal experience I tried this for a website years ago and it actually hurt my domain ranking. It was a real pain to get it sorted out too.
instead of purchasing,cant you get backlinks from websites that promise 10k backlinks will it hurt the ranking
creating too much pages with same content, put partner sites link in partner pages with too many links.