Certain traits are legally recognized as being immutable, or as being unfair to force or coerce someone to change in order to avoid harassing behavior. Under federal law, most commonly under Title VII of the Civil Rights Act of 1964, these traits fall into the following protected classes: race, color, religion, sex, national origin, sexual orientation, gender, gender identity and expression, disability, age, marital status, and pregnancy. The number of protected traits can surprise people. Many workers think that only sexual harassment can create a hostile working environment. That is not the case. While many workplaces are hostile because of sexual harassment, not all are.