What is a "nachgestellte Variable" in PHP and how can it be used effectively?

A "nachgestellte Variable" in PHP refers to concatenating a variable directly within a string without using the concatenation operator (.) or double quotes. This can be achieved by placing the variable name within curly braces {} inside the string. This technique can be used effectively to improve code readability and maintainability when dealing with complex string concatenations.

// Example of using nachgestellte Variable in PHP
$name = "John";
$age = 30;

// Using nachgestellte Variable for string concatenation
$message = "Hello, my name is {$name} and I am {$age} years old.";
echo $message;