In this example, we have an input field and a button that sends the value of the input field to a PHP script on the server using an XMLHttpRequest. In the PHP script, we process the input with a custom function and pass the result back to JavaScript using t3lib_div slashJS. In the JavaScript callback function, we can then access the result through the TYPO3.settings object. Package/library: t3lib_div slashJS is part of the TYPO3 CMS core library.