Cloaking is a measure to simulate a different content to search engine crawlers than to the actual internet user.
The goal is to achieve a highest possible position in the ranking of the search results. Technically the identification of the search query initiator is based on an evaluation of the IP-adress which provides information whether it is an engine or a normal user. As a result of IP-Delivery or User Agent Delivery the user will be provided with different contents.1)