The ADA statute identifies who is a person with a disability, who has obligations under the ADA, general non-discrimination requirements and other basic obligations. It delegates fleshing out those obligations to federal agencies. The agencies issue regulations and design standards. The regulations have the details on the rights of people with disabilities and responsibilities of employers, state and local governments, transportation providers, businesses and non-profit organizations. The design standards specify how many entrances need to be accessible, how many toilet rooms and the design for those elements.  To know what the ADA requires, you need to read the law, regulations and design standards.  

Federal law isn't the only consideration for businesses. Additionally, each state interprets the law differently. Consider the case against Netflix in 2012. Lawsuits were brought in federal court in Massachusetts and California. Netflix was accused of violating the ADA by not offering "closed captioning" options for its Internet streamed movies. Illustrating the complexity of this issue, the courts reached completely opposite decisions. Massachusetts held that Netflix must comply with the ADA, while the California court found that Netflix did not fall under the ADA's definition of "public accommodation."

Title II of the ADA prohibits discrimination against qualified individuals with disabilities in all programs, activities, and services of public entities. It applies to all state and local governments, their departments and agencies, and any other instrumentalities or special purpose districts of state or local governments. It clarifies the requirements of section 504 of the Rehabilitation Act of 1973, as amended, for public transportation systems that receive federal financial assistance, and extends coverage to all public entities that provide public transportation, whether or not they receive federal financial assistance. It establishes detailed standards for the operation of public transit systems, including commuter and intercity rail (e.g., AMTRAK).

Technology is changing, and many website designers are using creative and innovative ways to present web-based materials. These changes may involve new and different access problems and solutions for people with disabilities. This Chapter discusses just a few of the most common ways in which websites can pose barriers to access for people with disabilities. By using the resources listed at the end of this Chapter, you can learn to identify and address other barriers.
The trick to finding top web designers is to understand what you’re trying to build. There’s a big difference between designing a landing page meant to be the receiving end of a sales funnel and building an enterprise site that will serve corporate clients. The web designer is responsible for translating your unique brand identity into the visual elements that make up a website. The cost of your project will depend largely on your scope of work and the specific skills needed to bring your project to life.
Predictable: Websites should operate in ways that are familiar and predictable. When a new page element is in focus, the website should not initiate a change of context such as opening a new window or going to a new page. In addition, the website should warn of user-initiated changes of context ahead of time, for instance through the use of a submit button. Navigation and labeling should remain consistent between different pages.

Web developers need to keep this in mind when creating websites. The best screen readers use naturalized voices and alter tone and inflection based on HTML tags, so choose layout elements carefully. It is also important to keep in mind that navigation is significantly slower when using a screen reader than it is for sighted people. Sighted people don't have to wait for the reader to get to the link we want- we spot links quickly and are able to navigate to our sought items, often without having to do any reading at all. Minimizing graphics also helps shorten reading times and speed navigation for disabled users.
Title III of the Americans with Disabilities Act (ADA) requires that businesses and nonprofit services providers make accessibility accommodations to enable the disabled public to access the same services as clients who are not disabled. This includes electronic media and web sites. While the ADA applies to businesses with 15 or more employees, even smaller businesses can benefit from ensuring that their websites are ADA compliant. Doing so opens your company up to more potential clients and limits liability. Web developers should include ADA compliant features in the original site and application plans.
An employer cannot require you to take a medical examination before you are offered a job. Following a job offer, an employer can condition the offer on your passing a required medical examination, but only if all entering employees for that job category have to take the examination. However, an employer cannot reject you because of information about your disability revealed by the medical examination, unless the reasons for rejection are job-related and necessary for the conduct of the employer's business. The employer cannot refuse to hire you because of your disability if you can perform the essential functions of the job with an accommodation.
Navigable: Content that’s repeated on multiple pages can be easily skipped. All pages have informative titles, headings, and labels that describe the page’s content and hierarchy. Navigating the page must take place sequentially, in a meaningful order that preserves relationships on the page. All link text is descriptive in order to make clear where the link will take users. If users are navigating via a keyboard, the current focus of the keyboard is always highlighted and visible.
Hey Casey, this is one of the areas where things get a little weird because the W3 doesn’t actually have any say over the ADA guidelines, it is more than the ADA guidelines adopted the WCAG 2.0 guidelines as just that, a guideline to help. As far as I know, the tool you’ve linked to hasn’t been used in any judgements I’m aware of. Usually when it comes down to making a decision on if something is/isn’t compliant they have people use the actual PAWS tools and show what elements do/don’t work as intended or are otherwise inaccessible. Hope this helps!
The attorneys' fees provision of Title III does provide incentive for lawyers to specialize and engage in serial ADA litigation, but a disabled plaintiff does not obtain financial reward from attorneys' fees unless they act as their own attorney, or as mentioned above, a disabled plaintiff resides in a state that provides for minimum compensation and court fees in lawsuits. Moreover, there may be a benefit to these "private attorneys general" who identify and compel the correction of illegal conditions: they may increase the number of public accommodations accessible to persons with disabilities. "Civil rights law depends heavily on private enforcement. Moreover, the inclusion of penalties and damages is the driving force that facilitates voluntary compliance with the ADA."[56] Courts have noted:
As a result, most ADA suits are brought by a small number of private plaintiffs who view themselves as champions of the disabled. For the ADA to yield its promise of equal access for the disabled, it may indeed be necessary and desirable for committed individuals to bring serial litigation advancing the time when public accommodations will be compliant with the ADA."[57]