What common mistakes are made when comparing variables in PHP, as seen in the code provided?

One common mistake when comparing variables in PHP is using a single equal sign (=) instead of a double equal sign (==) or triple equal sign (===) for comparison. The single equal sign is used for assignment, not comparison. To fix this issue, ensure you use the correct comparison operator (== or ===) depending on the type of comparison you want to perform.

// Incorrect comparison using a single equal sign
$var1 = 5;
$var2 = 5;

if ($var1 = $var2) {
    echo "Variables are equal";
} else {
    echo "Variables are not equal";
}

// Correct comparison using double equal sign
if ($var1 == $var2) {
    echo "Variables are equal";
} else {
    echo "Variables are not equal";
}