Cloaking may be a computer program improvement (SEO) technique within which the content given to the computer program spider is completely different from that given to the user's browser. this is often done by delivering content supported the informatics addresses or the User-Agent HTTP header of the user requesting the page. once a user is known as a research engine spider, a server-side script delivers a special version of the online page, one that contains content not gift on the visible page, or that's gift however not searchable. the aim of cloaking is typically to deceive search engines in order that they show the page once it'd not preferably be displayed (black hat SEO). However, it can even be a practical (though antiquated) technique for informing search engines of content they might not preferably be ready to find as a result of it's embedded in non-textual containers like video or sure Adobe Flash elements.