{"id":20044,"date":"2020-01-28T13:22:45","date_gmt":"2020-01-28T13:22:45","guid":{"rendered":"https:\/\/www.arimetrics.com\/glosario-digital\/ajax"},"modified":"2026-09-24T22:09:21","modified_gmt":"2026-09-24T22:09:21","slug":"ajax","status":"publish","type":"encyclopedia","link":"https:\/\/www.arimetrics.com\/en\/digital-glossary\/ajax","title":{"rendered":"Ajax"},"content":{"rendered":"

\"Ajax\" Definition:<\/strong><\/p>\n

Ajax<\/strong> is a web development approach that allows data to be exchanged with a server and parts of a page to be updated without loading the entire document again. Its name comes from Asynchronous JavaScript and XML.<\/p>\n

It is neither a programming language nor a single technology.<\/strong> It combines browser features, JavaScript code, network requests, and updates to the displayed document. Although XML is part of the name, the response can use other formats, such as JSON, HTML, or text.<\/p>\n

Ajax usually runs asynchronously<\/strong> so that the application can remain responsive while it waits for the server. This does not mean that every operation is instantaneous or that data transfer is eliminated: it changes which part of the interface is updated and how the request is coordinated.<\/p>\n\n

Origin of the term Ajax<\/h2>\n

Jesse James Garrett introduced the term Ajax in 2005<\/strong> in the article Ajax: A New Approach to Web Applications<\/a>. The proposal grouped techniques that could already be used together to create more interactive web applications; it did not establish a separate language or standard.<\/p>\n

How Ajax works<\/h2>\n

The process begins when a user action or an application event starts a request.<\/strong> JavaScript<\/a> can make it through the Fetch API or XMLHttpRequest. When the response arrives, the program processes the data and modifies the necessary elements of the document, such as a results list, a confirmation message, or the contents of a shopping cart.<\/p>\n

The MDN guide to network requests<\/a> explains the use of Fetch and XMLHttpRequest. Fetch provides a promise-based interface<\/strong> and is common in current development. XMLHttpRequest remains available and provides specific capabilities, such as events for tracking the progress of certain transfers. Choosing one API or the other does not change the general meaning of Ajax.<\/p>\n

Ajax technologies and formats<\/h2>\n

The page presentation can be built with HTML<\/a> and CSS<\/a>, while JavaScript coordinates the request and the DOM update<\/strong>. The server can respond with JSON<\/a>, XML<\/a>, prepared HTML, or other content that both sides know how to interpret. Using JSON does not turn the technique into a separate concept called AJAJ.<\/p>\n

Ajax applications<\/h2>\n

Ajax is used for features such as search suggestions, form validation, pagination, product filters, dashboards that refresh data, and shopping cart operations. In all these cases, it can update a specific part of the interface<\/strong>, but it does not by itself determine how the experience should be designed or what information should be requested.<\/p>\n

Performance and accessibility<\/h2>\n

Partial updates do not guarantee a faster page.<\/strong> A large response, too many requests, or expensive processing can delay the interface. The application should represent loading and error states, prevent duplicate actions, and keep controls understandable for people who use a keyboard or assistive technologies.<\/p>\n

Security and navigation<\/h2>\n

Browser requests are subject to security rules.<\/strong> When a resource belongs to a different origin, the server must authorize access through CORS where appropriate. Ajax cannot bypass these restrictions or automatically provide access to any API.<\/p>\n

Changing content without a full navigation can affect browser history, URLs, and the ability to share or restore a state.<\/strong> These features need to be managed when relevant. Ajax describes communication and partial interface updates; it does not replace server behavior, accessibility, or navigation management.<\/p>\n","protected":false},"excerpt":{"rendered":"

Definition: Ajax is a web development approach that allows data to be exchanged with a server and parts of a page to be updated without loading the entire document again. Its name comes from Asynchronous JavaScript and XML. It is neither a programming language nor a single technology. It combines browser features, JavaScript code, network […]<\/p>\n","protected":false},"author":6,"featured_media":0,"template":"","encyclopedia-tag":[1275],"class_list":["post-20044","encyclopedia","type-encyclopedia","status-publish","hentry","encyclopedia-tag-data-exchange"],"_links":{"self":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/encyclopedia\/20044","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/encyclopedia"}],"about":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/types\/encyclopedia"}],"author":[{"embeddable":true,"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/users\/6"}],"wp:attachment":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/media?parent=20044"}],"wp:term":[{"taxonomy":"encyclopedia-tag","embeddable":true,"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/encyclopedia-tag?post=20044"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}