Cloaking is a black hat search engine optimization (SEO) technique to show search engines and human users different versions of the same website. Cloaking tricks the search engine into believing that the website content is relevant to the user’s query, when in reality it may be superficial, tangential, or even actively malicious.
Cloaking is a doorway page technique (creating web pages to deliberately manipulate search engine results, also known as spamdexing). Search engines penalize most instances of cloaking, up to and including removing cloaked websites from their indexes.
Types of cloaking
- IP-based cloaking: The website keeps a list of known search engine bot IPs and differentiates content based on the apparent IP of the visitor. IP-based cloaking should not be confused with IP delivery, which simply serves visitors different content based on their IP address (such as regional pricing, local news, and language preferences.)
- User-agent cloaking: The website loads content based on the visiting user-agent (the software active on the user’s behalf to retrieve data), differentiating between browser and search engine bot requests.
- Referrer cloaking: The website loads different content based on the referring domain of the entity making a request.