In PHP, what are some common mistakes developers make when comparing strings to integers or empty values, and how can these be avoided?

When comparing strings to integers or empty values in PHP, a common mistake developers make is using the `==` operator instead of `===`. The `==` operator performs type juggling, which can lead to unexpected results when comparing different data types. To avoid this issue, always use the strict comparison operator `===` to ensure both the value and type are the same.

// Incorrect comparison using ==
$string = "10";
$int = 10;

if ($string == $int) {
    echo "Equal";
} else {
    echo "Not Equal";
}

// Correct comparison using ===
if ($string === $int) {
    echo "Equal";
} else {
    echo "Not Equal";
}