Internet services allow access to huge amounts of information over the internet and can be categorized into four groups: communication services, information retrieval services, web services, and the world wide web. Communication services offer exchange of information between individuals or groups. Information retrieval services provide easy access to information on the internet. Web services allow applications to interact and exchange information over networks using standardized XML messaging. The world wide web, also known as W3, offers access to documents across servers using HTTP and allows users to navigate between pages with hyperlinks that integrate different types of media like text, images, sound and video.