Final answer:
The Civil Rights Act of 1866 specifically prohibits discrimination on the basis of race, while the Civil Rights Act of 1964 extends these protections to include race, color, religion, sex, and national origin.
Step-by-step explanation:
The Civil Rights Act of 1866 prohibits discrimination on the basis of race. This landmark legislation was designed to protect the rights of African Americans after the Civil War, ensuring all citizens are equally protected under the law. However, the Civil Rights Act of 1964, which is more comprehensive, prohibits discrimination in employment on several additional factors. According to Title VII of the Act, it is illegal to discriminate based on race, color, religion, sex, or national origin. This addresses multiple forms of discrimination and was a significant step forward in civil rights legislation in the United States.