Domain DNS propagation is a time, or delay, involved in sending your domain information to all other domain servers around the world. Names servers deliberately keep the addresses of domains in their memory for a period of time defined by the server name controller. This speeds up the process of checking a domain name address. Unfortunately this information is cached and resides in the name servers when it is converted to the original source information (domain registrar). Word servers refresh from once an hour to once a day. Normally 24 - 48 hours period is a good measure when DNS of any domain are changed to a domain registrar, after which everyone can see the change globally.