single and double quotes in php

Variables inside single quotes will not be executed
Double quotes will be executed
For example
$name = 'hello';
echo "the $name";
will output the hello
And if it is a single quote
$name = 'hello';
echo 'the $name';
will output the $name

The above introduces the single and double quotation marks in PHP, including the relevant content. I hope it will be helpful to friends who are interested in PHP tutorials.