What is the significance of using == instead of = in PHP comparisons?

Using == in PHP is used for comparison, while = is used for assignment. Using == ensures that you are comparing two values for equality, while = would mistakenly assign a value instead of comparing. This is important to prevent logical errors in your code and ensure that comparisons are done correctly.

// Incorrect usage of =
$variable1 = 5;
$variable2 = 10;

if($variable1 = $variable2) {
    echo "Variables are equal";
} else {
    echo "Variables are not equal";
}

// Correct usage of ==
$variable1 = 5;
$variable2 = 10;

if($variable1 == $variable2) {
    echo "Variables are equal";
} else {
    echo "Variables are not equal";
}