1. AJAX allows web applications to asynchronously retrieve and display data from a server without reloading the entire page. 2. AJAX can be used in Domino applications to dynamically retrieve data from the server like validating entries, looking up names, or getting category lists. 3. Making an AJAX request involves creating an XMLHttpRequest object, opening a GET request to a URL, setting an onreadystatechange handler, and sending the request. The response is then parsed as XML.