Since its birth in 1995, Wiki has become more and more popular. This paper presents a Semantic Wiki, a Wiki extended to include the ideas of Semantic Web. The proposed Semantic Wiki uses a simple Wiki syntax to write labeled links which represent RDF triples. By enabling the writing of labeled links, Semantic Wiki may provide an easy-to-use and flexible environment for an integrated management of content and metadata, so that Semantic Wiki may be used as a lightweight knowledge management system.