How can variable scope impact the initialization of variables in PHP scripts?

Variable scope can impact the initialization of variables in PHP scripts because variables declared outside a function have a global scope and can be accessed from within functions, while variables declared within a function have a local scope and cannot be accessed outside the function. To ensure variables are initialized properly, it's important to understand the scope in which they are declared and where they need to be accessed.

$globalVariable = "I am a global variable";

function testFunction() {
    $localVariable = "I am a local variable";
    echo $localVariable;
}

testFunction();
echo $globalVariable;