Equal to, Strictly equal to, Not equal to – DAX Guide

The “equal to” operator = returns TRUE when the two arguments have the same value.
https://dax.guide/op/equal-to/

The “strictly equal to” operator == returns TRUE when the two arguments have the same value or are both BLANK.
https://dax.guide/op/strictly-equal-to/

The “not equal to” operator returns TRUE when the two arguments do not have the same value.
https://dax.guide/op/not-equal-to/