Black hat seo are the techniques that are sometimes used to increase the page rank of a website but these techniques are considered illegal by the searching engines and if google finds that your website is using black hat seo to increase its page rank then google give a penalty to your websites. There are many black hat seo techniques but the famous ones are mentioned below:
- Keyword Stuffing
- Cloaking
- Doorway Pages or Gateway Pages
- Duplicate Content or Mirror Site
- Blog Spam or Comment Spam