Описание тега hig
https://en.wikipedia.org/wiki/Human_interface_guidelines are user-interface design documents specifying behavior of gui elements. They contain recommendations for how to achieve a consistent experience between programs on a platform.
Human interface guidelines (HIG) are software development documents which offer application developers a set of recommendations. Their aim is to improve the experience for the users by making application interfaces more intuitive, learnable, and consistent.
Human interface guidelines often describe the visual design rules, including icon and window design and style. Frequently they specify how user input and interaction mechanisms work. Aside from the detailed rules, guidelines sometimes also make broader suggestions about how to organize and design the application and write user-interface text.
HIGs are also done for applications. In this case the HIG will build on a platform HIG by adding the common semantics for a range of application functions.
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