5.1.1 Addresses on the web

• URL (Uniform Resource Locator)


  The unique name given to each resource on the web, made up of several parts
• URL


  • Scheme name
  • Host name
  • Path name
• Scheme name


  Defines how the client browser should form its requests to access the resource server
• Scheme names


  • http
  • https
• Host name


  The name of the server that holds the web page
• Many computers that serve web pages have names that begin with 'www', but that's entirely optional
• Path name


  The name of the file on the server that contains the web page
• Domain name


  The 'top level' name, such as wikipedia.org or open.ac.uk, while the various associated 'lower level' servers have specific host names
• Top-level country domain names

  • .at
  • .au
  • .be
  • .br
  • .ch
  • .ca
  • .de
  • .dk
  • .es
  • .eu
  • .hu
  • .ie
  • .jp
  • .ru
  • .za
• The top-level country domain name for the United Kingdom is .uk
• ISO 3166-1 alpha-2 is the international standard for country domain names
• Adherence to standards improves safety, reliability and quality, and ensures consistency between manufacturers, providers and developers
• If a link no longer works

  You can try deleting characters from the end of the URL to find the correct page
• Some servers are configured to display a default page like 'index.html' or 'default.html' when trying to access a folder
• Some web addresses like bt.com, bl.uk or open.ac.uk can be used instead of the full path name
• The W3C is an international consortium that aims to ensure the long-term development of the web and creates standards like HTML