Prohibited discrimination may include, among other things, firing or refusing to hire someone based on a real or perceived disability, segregation, and harassment based on a disability. Covered entities are also required to provide reasonable accommodations to job applicants and employees with disabilities.[16] A reasonable accommodation is a change in the way things are typically done that the person needs because of a disability, and can include, among other things, special equipment that allows the person to perform the job, scheduling changes, and changes to the way work assignments are chosen or communicated.[17] An employer is not required to provide an accommodation that would involve undue hardship (significant difficulty or expense), and the individual who receives the accommodation must still perform the essential functions of the job and meet the normal performance requirements. An employee or applicant who currently engages in the illegal use of drugs is not considered qualified when a covered entity takes adverse action based on such use.[18]
People with disabilities that affect their sight, hearing, or mobility may have difficulty accessing certain parts of websites and other online properties unless certain accommodations are made. Just as businesses may need to make adjustments to their physical location so that disabled customers have easy access to the premises, companies may need to adjust certain aspects of their websites so individuals with disabilities can take full advantage of all the features and services.

UPDATE: Since writing this post in August 2017, several important changes have taken place in the laws regarding ADA compliance for websites. On December 26, 2017, the Department of Justice announced that they have withdrawn the Obama-era Advance Notice of Proposed Rulemaking mentioned in this article which intended to require ADA website compliance. The DOJ’s withdrawal announcement stated, “The Department will continue to assess whether specific technical standards are necessary and appropriate to assist covered entities with complying with the ADA.”
The ADA requires that title II entities (State and local governments) and title III entities (businesses and nonprofit organizations that serve the public) communicate effectively with people who have communication disabilities. The goal is to ensure that communication with people with these disabilities is equally effective as communication with people without disabilities.
Shortly before the act was passed, disability rights activists with physical disabilities coalesced in front of the Capitol Building, shed their crutches, wheelchairs, powerchairs and other assistive devices, and immediately proceeded to crawl and pull their bodies up all 100 of the Capitol's front steps, without warning.[38] As the activists did so, many of them chanted "ADA now", and "Vote, Now". Some activists who remained at the bottom of the steps held signs and yelled words of encouragement at the "Capitol Crawlers". Jennifer Keelan, a second grader with cerebral palsy, was videotaped as she pulled herself up the steps, using mostly her hands and arms, saying "I'll take all night if I have to." This direct action is reported to have "inconvenienced" several senators and to have pushed them to approve the act. While there are those who do not attribute much overall importance to this action, the "Capitol Crawl" of 1990 is seen by some present-day disability activists in the United States as a central act for encouraging the ADA into law.[39]

In some circumstances, longer and more detailed text will be necessary to convey the same meaningful information that other visitors to the website can see. For example, a map showing the locations of neighborhood branches of a city library needs a tag with much more information in text format. In that instance, where the map conveys the locations of several facilities, add a “longdesc” tag that includes a text equivalent description of each location shown on the map – e.g., “City Center Library, 433 N. Main Street, located on North Main Street between 4th Avenue and 5th Avenue.”

The fastest, most certain way to be sure your website is in compliance is to contact a qualified web design agency and have them perform an audit of all your online properties. Make sure you interview the agency thoroughly first, as not all agencies are up to speed on ADA website compliance rules. A qualified web design firm will be able to identify any violations of ADA Website Compliance and outline a plan for updating your online content and properties. 
We recommend following the Web Content Accessibility Guidelines (WCAG) as best practice on your site, which is what our platform uses as the foundation for our accessibility guidelines. To see how accessible your site is according to WCAG, request a website audit using the form on this page. Your PDF report will be emailed to you within one business day, so you can start assessing the conformance of your site quickly. 
For most businesses, the need for ADA web compliance means they will need to make at least some adjustments to all of their online marketing strategies. For instance, if your company provides tax preparation services, all of the tax forms you provide for customers to download would need to meet accessibility standards. Any online tax preparation services that you offer would also need to be configured so they meet ADA standards, as would your mobile app.
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