PHP is the programming language that WordPress is written in. You do not need to know any PHP to use WordPress, but knowing even a little can make it easy to perform minor customizations without a programmer.
If you’re curious, here are a few sample lines of PHP code:
function hello_dolly() {
$chosen = hello_dolly_get_lyric();
echo " <p id='dolly'>$chosen </p>";
}
Here are two things you should know about PHP:
1) To install and run WordPress, your hosting company has to be running PHP version 5.2.4 or greater, and MySQL version 5.0 or greater. But the recommended version of PHP is version 7 or greater because it is so much faster, more secure, and still being supported with updates.
2) If you get a PHP error while trying to use your WordPress site, ask your hosting company or web developer for help.