Hlo Friends,
Name few Black Hat SEO techniques?

Keyword Stacking and Keyword Stuffing.
Tiny Text, Hidden Text, and Hidden Links.
Cloaking.
Doorway Pages or Gateway Pages.
Duplicate Content or Mirror Site.
Spam Blogs or Splogs.

Blackhat SEO include keyword stuffing, invisible text and doorway pages, clocking, link
spamming, duplicate sites, paid link, link farming, scraping, title staking

    Unrelated Keywords. ...
    Keyword Stacking and Keyword Stuffing. ...
    Tiny Text, Hidden Text, and Hidden Links. ...
    Cloaking. ...
    Doorway Pages or Gateway Pages. ...
    Bait-and-Switch or Page Swapping. ...
    Duplicate Content or Mirror Site. ...
    Spam Blogs or Splogs.

Duplicate content
Duplicate website
Cloaking
Keyword Stuffing

Cloaking. and Doorway Pages

Keyword Stacking and Keyword Stuffing.
Tiny Text, Hidden Text, and Hidden Links.
Unrelated Keywords.
Doorway Pages or Gateway Pages.
Duplicate Content or Mirror Site.
Bait-and-Switch or Page Swapping.
Spam Blogs or Splogs.
Cloaking.

Few techniques of Black Hat SEO are :

Keyword Stacking and Keyword Stuffing
Tiny Text, Hidden Text, and Hidden Links
Cloaking
Doorway Pages or Gateway Pages
Bait-and-Switch or Page Swapping
Duplicate Content or Mirror Site
Spam Blogs or Splogs
Trackback Spam
Blog Spam or Comment Spam
Social Networking Spam
Spam Ping or Sping or Pingback Spam
Referrer Spam
Link Farms
Cookie Stuffing or Cookie Dropping
Typosquatting or URL Hijacking

Tiny Text, Hidden Text, and Hidden Links.Cloaking.Doorway Pages or Gateway Pages.Duplicate Content

Black hat seo techniques help to rank your keywords faster in search engines and generates more traffic in shorter time. But the methods followed are not supported by Google and hence your website can get penalized for following such techniques.

Cloaking,link farming ,Duplicate Content are the black hat seo techniques

Keyword stuffing
Duplicate Content
Cloaking

Doorway Pages or Gateway Pages
Unrelated Keywords
Keyword Stacking
Keyword Stuffing
Hidden Text
Tiny Text
Hidden Links
Cloaking