what is the difference between = and ==?

Answer 1

= is assignment operator, it assign right operand to left operand. And == is an equality operator is checks that, whether left and right operands are equal to or not. If equal then result true(1) if not then false(0).

Answer 2

= asings the right value to the left variable. == is used to show if a variable's value is equal to the value on the right, usually used in if statements.