Article 9 of the UN CRPD defines accessibility and its importance for people with disabilities. Accessibility refers to the ability to reach, understand, or approach something and involves removing barriers. There are four main forms of barriers - physical, informational, institutional, and attitudinal. Physical barriers involve the built environment and infrastructure. Informational barriers relate to how information is presented not being accessible to people with various disabilities. Institutional barriers are laws and practices that prohibit or fail to facilitate access. Attitudinal barriers stem from societal myths and stereotypes unconsciously creating barriers or a lack of awareness about the needs of people with disabilities. The CRPD requires countries to promote accessibility in their legislation, policies and programs.