Description: For example, when you enter a search query on Google, a tooltip with possible variants of the query is displayed. On many sites when registering a user enters a name and immediately sees whether that name is available or not.
AJAX is a term that describes how to use existing technology to receive data from the server in the background and use it to update the page (without reloading).
Page reloading is a big hurdle in Web application development for Java developers.
AJAX is an acronym that stands for Asynchronous Javascript and XML. In fact, AJAX is not a new technology, because both Javascript and XML have existed for quite some time