What happens if an exception is thrown in the application?

When an exception is thrown in a PHP application (throw new Exception()), the following occurs:

1. The current execution thread is interrupted at the point where the exception is thrown.
2. PHP begins searching for the nearest try-catch block that can handle this exception.
3. If such a block is found, control is transferred to the corresponding catch, where the error can be handled.
4. If no catch is found, the exception continues to propagate up the call stack.
5. If no catch handles the exception, the script terminates with a fatal error, and an error message is displayed.

Example:

try {
    throw new Exception("Error!");
} catch (Exception $e) {
    echo "Caught exception: " . $e->getMessage();
}

Thus, exceptions allow centralized error handling and control over the execution flow when unforeseen situations occur.