With tagging, the readers of a Web resource (typically a Web page or a photograph posted on a photo-posting site) can associate a word or
phrase with that resource; the resource can then be found by searching for that tag. Tagging is catching on with early adopters. It is likely
to go mainstream because it empowers readers, it is social and it has business benefits. As tagging becomes popular, it will face challenges,
including increased ambiguity of tags and tag spam.