How to understand this writing in php-CodePudding

I saw this code when I was learning php through the source code, but I didn't understand this way of writing. What is the official name of this writing in php

CodePudding user response：

The given code example does nothing else as printing the given HTML elements.

function disinfo() {
?><h1>i muss you</h1><?
}

disinfo(); // results into <h1>i miss you</h1>

The declaration interrupts PHP and falls back into pure HTML. PHP has always been able to be written as a quasi template engine with HTML elements in a file that is interpretable by PHP. You do not even have to echo the markup. Since PHP is interupted with an ending delimiter and starts again with a starting delimiter everything in between is simply interpreted as html.

In fact there is no official name for this kind of output.