Ajax

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AJAX stands for Asynchronous Javascript and XML. It is a group of interrelated web development techniques used to create interactive web applications.

The mostly on Javascript based techniques allow to have web pages which load data in the background and update their content accordingly. Without Ajax this would require a page reload.

An example would be a web page with a table of all members of an organization. A filter in form of a select box on top of the table allow the user to select only members of a certain region. Instead of reloading the table with only members of this region Ajax allows to ask the server in the background for those members and to update the table after retreival of the data.

Despite the name, the use of JavaScript and XML is not actually required, nor do the requests need to be asynchronous. The acronym AJAX has thus changed to the term Ajax, which does not represent these specific technologies.