Case law has been the most helpful in illuminating the implications of the ADA for websites.There have been lawsuits involving companies like Expedia,, Southwest Airlines, and Target as defendants and primarily featuring accessibility organizations as plaintiffs. These cases had mixed results, but each helped clarify the ADA's jurisdiction on the web. 
You probably won't have to check your site with all of the available evaluation tools out there, but it is a good idea to do so for the most common web browsers. Just as accessibility software makes it easier for people with disabilities to navigate the Internet, these tools make it easier for developers to ensure accessibility from the start. When you think you've mastered it, go back through the Section 508 compliance checklist to ensure you've met every goal.

The type of operating system and hosting doesn’t matter much for design, but the platform is a factor. For instance, if you need a WordPress theme, the designer must work with WordPress themes and customize them in a way that a developer can feasibly code in CSS or JavaScript on the front end. If you use another CMS, the developer must work with those elements. Most designers specialize in specific platforms, so review their portfolios and experience for specific platforms before you invite them to bid on your project.
These and other types of multimedia can present two distinct problems for people with different disabilities. People who are deaf or hard of hearing can generally see the information presented on webpages. But a deaf person or someone who is hard of hearing may not be able to hear the audio track of a video. On the other hand, persons who are blind or have low vision are frequently unable to see the video images but can hear the audio track.
This is the reason why I think web design firms have to position themselves as solution providers and not just web guys/gals. A client doesn't need a website, they need sales. The website is just part of that solution but it's not the solution and unlike web design, service like email marketing automation, SEO, and PPC requires an experienced professional.
Title II applies to public transportation provided by public entities through regulations by the U.S. Department of Transportation. It includes the National Railroad Passenger Corporation (Amtrak), along with all other commuter authorities. This section requires the provision of paratransit services by public entities that provide fixed-route services. ADA also sets minimum requirements for space layout in order to facilitate wheelchair securement on public transport.[20]

Webpage designers often have aesthetic preferences and may want everyone to see their webpages in exactly the same color, size and layout. But because of their disability, many people with low vision do not see webpages the same as other people. Some see only small portions of a computer display at one time. Others cannot see text or images that are too small. Still others can only see website content if it appears in specific colors. For these reasons, many people with low vision use specific color and font settings when they access the Internet – settings that are often very different from those most people use. For example, many people with low vision need to use high contrast settings, such as bold white or yellow letters on a black background. Others need just the opposite – bold black text on a white or yellow background. And, many must use softer, more subtle color combinations.

Under 2010 revisions of Department of Justice regulations, newly constructed or altered swimming pools, wading pools, and spas must have an accessible means of entrance and exit to pools for disabled people. However, the requirement is conditioned on whether providing access through a fixed lift is "readily achievable". Other requirements exist, based on pool size, include providing a certain number of accessible means of entry and exit, which are outlined in Section 242 of the standards. However, businesses are free to consider the differences in the application of the rules depending on whether the pool is new or altered, or whether the swimming pool was in existence before the effective date of the new rule. Full compliance may not be required for existing facilities; Section 242 and 1009 of the 2010 Standards outline such exceptions.[21]

Title IV of the ADA amended the landmark Communications Act of 1934 primarily by adding section 47 U.S.C. § 225. This section requires that all telecommunications companies in the U.S. take steps to ensure functionally equivalent services for consumers with disabilities, notably those who are deaf or hard of hearing and those with speech impairments. When Title IV took effect in the early 1990s, it led to the installation of public teletypewriter (TTY) machines and other TDD (telecommunications devices for the deaf). Title IV also led to the creation, in all 50 states and the District of Columbia, of what was then called dual-party relay services and now are known as Telecommunications Relay Services (TRS), such as STS relay. Today, many TRS-mediated calls are made over the Internet by consumers who use broadband connections. Some are Video Relay Service (VRS) calls, while others are text calls. In either variation, communication assistants translate between the signed or typed words of a consumer and the spoken words of others. In 2006, according to the Federal Communications Commission (FCC), VRS calls averaged two million minutes a month.

Input Assistance: When users are entering input into the website, any input errors are automatically detected and written out, providing, for instance, text descriptions that identify fields that were not filled out or data that was in the wrong format. The website also provides suggestions to fix the errors. Input fields and buttons are labeled to provide their functions and instructions. If the user’s input is being used for legal purposes or financial transactions, then the user must be able to reverse submissions or correct errors.

ADA compliance isn’t a set-it-and-forget-it thing. Compliance standards must be followed and will evolve just as your website does. There are guidelines all website contributors must know to stay within ADA guidelines. It is generally not burdensome but it does require some web managers to change their workflows. For example, loading images up to your ecommerce site will always need some of that alternative text (alt tags) mentioned above.
The ADA itself holds different organizations to more/less stringent standards based on a host of factors, government funding being a major one. Government agencies themselves are usually held to the most severe standards. That said, while ADA has adopted WCAG as the defacto standard, from what I’ve seen it appears they’re going with AA compliance as the most reliable one. That said, we’ve done work with some organizations who’ve chosen to comply with AAA in an effort to be as buttoned up as possible from an accessibility and experiential perspective. We’ve also worked with some who have tighter budgers and aim for level A compliance and have a more “react and repair” mindset when they discover anything in their site that is giving someone hardship from an accessibilirt standpoint.
Web design is not the same as web development, but sometimes you’ll find a developer or designer with overlapping skills who can perform both. Many web designers create mock-ups of a site or app using graphic design software, while others create custom themes that can be viewed as functional websites. A website designer typically works with a variety of design software and technologies to create responsive layouts and page elements that are visually appealing to users. They’ll work to improve the interface and user experience, and often collaborate with graphic artists, programmers and copywriters along the way.

This was a case filed before The United States District Court for the Eastern District of Michigan Southern Division on behalf of the Michigan Paralyzed Veterans of America against University of Michigan – Michigan Stadium claiming that Michigan Stadium violated the Americans with Disabilities Act in its $226-million renovation by failing to add enough seats for disabled fans or accommodate the needs for disabled restrooms, concessions and parking. Additionally, the distribution of the accessible seating was at issue, with nearly all the seats being provided in the end-zone areas. The U.S. Department of Justice assisted in the suit filed by attorney Richard Bernstein of The Law Offices of Sam Bernstein in Farmington Hills, Michigan, which was settled in March 2008.[66] The settlement required the stadium to add 329 wheelchair seats throughout the stadium by 2010, and an additional 135 accessible seats in clubhouses to go along with the existing 88 wheelchair seats. This case was significant because it set a precedent for the uniform distribution of accessible seating and gave the DOJ the opportunity to clarify previously unclear rules.[67] The agreement now is a blueprint for all stadiums and other public facilities regarding accessibility.[68]