anchor.diff: -[[{chapter}.websocket-intro]]
  +[id={chapter}.websocket-intro]
   = Introduction to WebSocket
   
   The WebSocket protocol, https://tools.ietf.org/html/rfc6455[RFC 6455], provides a standardized
  
positive.code: 
  
  
  [[{chapter}.websocket-intro-when-to-use]]
  == When to Use WebSockets
  
  WebSockets can make a web page be dynamic and interactive. However, in many cases,
  
negative.code: 
  
  
  [id={chapter}.websocket-intro-architecture]
  == HTTP Versus WebSocket
  
  Even though WebSocket is designed to be HTTP-compatible and starts with an HTTP request,
  