What are the potential pitfalls of not initializing variables in PHP, and how does it differ between typed and untyped syntax?

Not initializing variables in PHP can lead to unexpected behavior and errors, especially when trying to use variables that have not been assigned a value. In untyped syntax, uninitialized variables default to a null value, which can cause issues if not handled properly. In typed syntax, uninitialized variables will throw a TypeError, making it easier to catch and fix the issue before it causes problems.

// Untyped syntax
$uninitializedVar = null; // Initialize variable with a default value

// Typed syntax
int $uninitializedVar; // Initialize variable with a type declaration