Level AA is a little more significant, and makes sites accessible to people with a wider range of disabilities, including the most common barriers to use. It won't impact the look and feel of the site as much as Level AAA compliance, though it does include guidance on color contrast and error identification. Most businesses should be aiming for Level AA conformity, and it appears to reflect the level of accessibility the DOJ expects. 
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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]
One of the first major ADA lawsuits, Paralyzed Veterans of America v. Ellerbe Becket Architects and Engineers (PVA 1996) was focused on the wheelchair accessibility of a stadium project that was still in the design phase, MCI Center (now known as Capital One Arena) in Washington, D.C. Previous to this case, which was filed only five years after the ADA was passed, the DOJ was unable or unwilling to provide clarification on the distribution requirements for accessible wheelchair locations in large assembly spaces. While Section 4.33.3 of ADAAG makes reference to lines of sight, no specific reference is made to seeing over standing patrons. The MCI Center, designed by Ellerbe Becket Architects & Engineers, was designed with too few wheelchair and companion seats, and the ones that were included did not provide sight lines that would enable the wheelchair user to view the playing area while the spectators in front of them were standing. This case[69][70] and another related case[71] established precedent on seat distribution and sight lines issues for ADA enforcement that continues to present day.
In 2001, for men of all working ages and women under 40, Current Population Survey data showed a sharp drop in the employment of disabled workers, leading at least two economists to attribute the cause to the Act.[52] By contrast, a study in 2003 found that while the Act may have led to short term reactions by employers, in the long term, there were either positive or neutral consequences for wages and employment.[53] In 2005 the rate of employment among disabled people increased to 45% of the population of disabled people.[54]
The ADA defines a covered disability as a physical or mental impairment that substantially limits one or more major life activities, a history of having such an impairment, or being regarded as having such an impairment. The Equal Employment Opportunity Commission (EEOC) was charged with interpreting the 1990 law with regard to discrimination in employment. The EEOC developed regulations limiting an individual's impairment to one that "severely or significantly restricts" a major life activity. The ADAAA directed the EEOC to amend its regulations and replace "severely or significantly" with "substantially limits", a more lenient standard.[42]
Since enforcement of the act began in July 1992, it has quickly become a major component of employment law. The ADA allows private plaintiffs to receive only injunctive relief (a court order requiring the public accommodation to remedy violations of the accessibility regulations) and attorneys' fees, and does not provide monetary rewards to private plaintiffs who sue non-compliant businesses. Unless a state law, such as the California Unruh Civil Rights Act,[55] provides for monetary damages to private plaintiffs, persons with disabilities do not obtain direct financial benefits from suing businesses that violate the ADA.
Blind people, those with low vision, and people with other disabilities that affect their ability to read a computer display often use different technologies so they can access the information displayed on a webpage. Two commonly used technologies are screen readers and refreshable Braille displays. As discussed above, a screen reader is a computer program that speaks the text that appears on the computer display, beginning in the top-left corner. A refreshable Braille display is an electronic device that translates text into Braille characters that can be read by touch. These assistive technologies read text. They cannot translate images into speech or Braille, even if words appear in the images. For example, these technologies cannot interpret a photograph of a stop sign, even if the word “stop” appears in the image.

While legal considerations might be your biggest worry, making your site more accessible is simply good customer service. More than 39 million Americans are blind and another 246 million have "low vision," Another one million are deaf in the U.S. Add to that people with mobility issues that prevent them from using their hands and that's a huge portion of the country's buying power.