The Americans with Disabilities Act of 1990 or ADA (42 U.S.C. § 12101) is a civil rights law that prohibits discrimination based on disability. It affords similar protections against discrimination to Americans with disabilities as the Civil Rights Act of 1964, which made discrimination based on race, religion, sex, national origin, and other characteristics illegal. In addition, unlike the Civil Rights Act, the ADA also requires covered employers to provide reasonable accommodations to employees with disabilities, and imposes accessibility requirements on public accommodations.
There have been some notable cases regarding the ADA. For example, two major hotel room marketers (Expedia.com and Hotels.com) with their business presence on the Internet were sued because its customers with disabilities could not reserve hotel rooms, through their websites without substantial extra efforts that persons without disabilities were not required to perform. These represent a major potential expansion of the ADA in that this, and other similar suits (known as "bricks vs. clicks"), seeks to expand the ADA's authority to cyberspace, where entities may not have actual physical facilities that are required to comply.
Once you have been hired and started work, your employer cannot require that you take a medical examination or ask questions about your disability unless they are related to your job and necessary for the conduct of your employer's business. Your employer may conduct voluntary medical examinations that are part of an employee health program, and may provide medical information required by State workers' compensation laws to the agencies that administer such laws.