How should GET parameters be properly formatted in PHP scripts to avoid unexpected errors or issues?

Improperly formatted GET parameters in PHP scripts can lead to unexpected errors or security vulnerabilities. To avoid these issues, it is important to properly sanitize and validate any incoming GET parameters before using them in your script. This can be done by using PHP's built-in functions like `filter_input()` or `htmlspecialchars()` to sanitize the input and prevent any malicious code from being executed.

// Example of properly formatting GET parameters in PHP script
$param1 = filter_input(INPUT_GET, 'param1', FILTER_SANITIZE_STRING);
$param2 = filter_input(INPUT_GET, 'param2', FILTER_SANITIZE_NUMBER_INT);

// Now you can safely use $param1 and $param2 in your script without worrying about unexpected errors or security issues