Explain Black Hat SEO techniques?

[Nekurokaze]

Let see, we can classified them like this:
- Black Hat SEO - guys who will do anything to gain traffic (such as spamming/duplicating) in short time. The good thing is they can get considerable amount of traffic in short term, but in the long term it is not stable. Just like the recent google penguin updates, it really messes Black Hat up.

- White Hat SEO - 'good guys' who focus on doing good and variety of content, contributing organic/natural traffic rate.

- Grey Hat SEO - guys who do both White Hat and Black Hat, but some say that they are Black Hat disguised as White Hat.