A web site is a collection of web pages, images, videos and other digital assets that is hosted on a web server, usually accessible via the Internet. A web page is a document, typically written in HTML, that is almost always accessible via HTTP, a protocol that transfers information from the web server to display in the user's web browser. All publicly accessible websites are seen collectively as constituting the World Wide Web. The pages of websites can usually be accessed from a common root URL called the homepage, and usually reside on the same physical server. The URLs of the pages organize them into a hierarchy, although the hyperlinks between them control how the reader perceives the overall structure and how the traffic flows between the different parts of the sites. The web pages can be uploaded via File Transfer Protocol (FTP) to the web server that allows individuals and organizations to provide their own web sites accessible via Internet. One can set up his own web site by himself (with a little understanding of html) or call upon a web-designer to do the job.