Black Hat SEO describes the use of unethical or deceptive optimization techniques. This includes spam, cloaking, or violating search engine rules.

These include:

• Websites that consist mainly of scraped content
• Doorway pages or cloaked sites and false redirects i.e. the search result contents do not match the page displayed to users.
• Keyword stuffing and pages containing many irrelevant words
• Hidden text and/or hidden links
• Sites that contain misspellings or extended spellings of well-known websites

While there may be short term gains from black-hat techniques, it is important to be aware that any of these practices when discovered may lead to the website being banned or penalised by the search engines.