9.2 ("Web content requirements") of the European standard EN 301 549 published by ETSI. EN 301 549 was produced in response to a mandate that the European Commission gave to the three official European standardisation bodies (CEN, CENELEC and ETSI) and is the first European standard for ICT products and services. WCAG 2.1 became a W3C Recommendation on 5 June 2018. As of September 2022, WCAG 2.2 is a W3C candidate recommendation snapshot, and is scheduled to be finalized within 2022. Version 3 (2021-present) At the end of 2021, the Accessibility Guidelines Working Group announced that they will be introducing a new colour contrast guide as part of their WCAG 3.0 update called Advanced Perceptual Contrast Algorithm (APCA). WCAG 3.0 will replace the older WCAG 2.0 method and provide a range of recommendations for making web content more accessible. Versions Version 1 WCAG 1.0 consist of 14 guidelines—each of which describes a general principle of accessible design. Each guideline covers a basic theme of web accessibility and is associated with one or more checkpoints that describes how to apply that guideline to particular webpage features. Guideline 1: Provide equivalent alternatives to auditory and visual content Guideline 2: Don't rely on colour alone Guideline 3: Use markup and style sheets, and do so properly Guideline 4: Clarify natural language usage Guideline 5: Create tables that transform gracefully Guideline 6: Ensure that pages featuring new technologies transform gracefully Guideline 7: Ensure user control of time sensitive content changes Guideline 8: Ensure direct accessibility of embedded user interfaces Guideline 9: Design for device independence Guideline 10: User interim solutions Guideline 11: Use W3C technologies and guidelines Guideline 12: Provide context and orientation information Guideline 13: Provide clear navigation mechanisms Guideline 14: Ensure that documents are clear and simple Each of the in total 65 WCAG 1.0 checkpoints has an assigned priority level based on the checkpoint's impact on accessibility: Priority 1: Web developers must satisfy these requirements, otherwise it will be impossible for one or more groups to access the Web content. Conformance to this level is described as A. Priority 2: Web developers should satisfy these requirements, otherwise some groups will find it difficult to access the Web content. Conformance to this level is described as AA or Double-A. Priority 3: Web developers may satisfy these requirements to make it easier for some groups to access the Web content. Conformance to this