Web Accessibility, often abbreviated as a11y, is the inclusive practice of designing and developing websites and applications to be usable by everyone, particularly people with disabilities. It addresses a wide spectrum of impairments, including visual, auditory, motor, and cognitive challenges, by implementing specific technical and design standards outlined in guidelines like the Web Content Accessibility Guidelines (WCAG). Key practices include providing alternative text for images, ensuring full keyboard navigability, maintaining sufficient color contrast, and captioning videos, all with the goal of removing barriers to ensure that all users have equal access to information and functionality on the web.