ISO/IEC TR 13066-4:2015 provides an overview to the structure and terminology of the Linux/UNIX graphical environments accessibility API.

It will provide the following:

- a description of the overall architecture and terminology of the API;

- further introductory explanations regarding the content and use of the API beyond those found in ISO/IEC 13066‑1:2011, Annex A;

- an overview of the main properties, including

• - of user interface elements,
• - of how to get and set focus, and
• - of communication mechanisms in the API;

- a discussion of design considerations for the API (e.g. pointers to external sources of information on accessibility guidance related to using the API);

- information on extending the API (and where this is appropriate);

- an introduction to the programming interface of the API (including pointers to external sources of information).

It will provide this information as an introduction to the Java API to assist the following:

- IT system level developers who create custom controls and/or interface to them;

- AT developers involved in programming "hardware to software" and "software to software" interactions.