The Web Content Accessibility Guidelines (WCAG) 2.1 is an international standard that provides guidelines for making web content more accessible to people with disabilities, including visual, auditory, motor, and cognitive impairments. Following these guidelines is important because it ensures that all website visitors, regardless of their abilities, can access and use the website's content and functionality.

By following the WCAG 2.1 guidelines, websites can be designed and developed in a way that makes them more usable for people with disabilities. This can include providing alternative text for images, ensuring that text has a high contrast ratio, and providing clear and descriptive labels for buttons and form controls. Additionally, by using semantic HTML tags, CSS, and ARIA roles, the structure and purpose of the website's content can be conveyed to assistive technologies such as screen readers.

Ensuring that the website's functionality is operable through a keyboard, providing clear instructions and error messages, and testing the website with a variety of assistive technologies are also key steps in following the WCAG 2.1 guidelines.

By following these guidelines, website can be more inclusive, meeting the needs of a wider range of users, including those with disabilities. And it also can help website to avoid legal issues and to meet legal requirements.

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