What is cloaking?
Cloaking is the concept of delivering one — usually keyword-heavy — Web page to a search engine for indexing, while serving an entirely different page to everyone else, to trick the search engine into thinking that it is selecting a prime match for a search request.
Many search engines consider cloaking to be an act of spamming. If cloaking is detected, Web pages may be temporarily or permanently removed from the search engine listings. At the very least, the ranking that was gained through cloaking disappears. Therefore, Web developers are generally advised not to use cloaking as a means to boost search engine rankings.
Usually, search engines catch cloaked pages by revisiting indexed sites. Because there is no exact way to predict a search engine's revisiting intervals, Web site owners who use cloaking to secure their search engine rankings get caught sooner or later.