Discrimination is the unequal treatment of people based on identifiable characteristics. Some types of discrimination are illegal, and there are policies against other types in government agencies and public organizations. Many of the legal provisions are based on the 1964 Civil Rights Act. Discrimination in the workplace is regulated to ensure that people have equal access to jobs and equal benefits once hired.
Title VII of the Civil Rights Act prohibits discrimination based on race or color and specifically makes race-based employment decisions illegal. You can't hire people based on race or color, and once hired, you can't make decisions to promote employees, give them raises and benefits, and assign responsibilities based on race or color. For example, it is discrimination to hire a white or light-skinned person rather than a non-white applicant who has better qualifications. When considering salaries or promotion, it is discrimination to give raises or promotions to one racial group over others who performed equally well.
Legislation outlawing sexual discrimination in the workplace addresses what work women can do and wages. You have to pay men and women equally for the same work, and you are not allowed to treat women differently based on their sex. The legislation includes a prohibition against discrimination because of pregnancy or marital status, and forbids sexual harassment in the workplace. It is discrimination to refuse applications from women for particular jobs and to pay them less for equal work than men. Discrimination includes limiting promotions or pay because of pregnancy or possible pregnancy and permitting sexually inappropriate language or behavior in the workplace.
In 1967 the Age Discrimination in Employment Act extended prohibitions against discrimination to people over 40. The act makes it illegal to treat people over 40-years-old differently because of their age, and applies to employers with over 20 employees. As an employer, you are not allowed to discriminate against a person due to his age in hiring, compensation, firing, job assignments or training decisions. Giving preferred assignments to younger people or giving them training not available to older employees is discriminatory.
The 1990 Americans with Disabilities Act requires employers to consider people with disabilities for employment on the same basis as everyone else, as long as they are able to carry out the work. This means you are not allowed to refuse to hire someone because she is in a wheelchair and you have to accommodate her needs when considering her for promotion. It is discrimination to refuse to hire a blind person if the work doesn't require sight or a deaf person if his work doesn't require hearing. Once you have hired a wheelchair-bound person, it is discrimination to refuse to install wheelchair ramps if they are needed for a particular job.