Most of the lowercase abbreviations are just the names of device drivers or platforms. VK is just Vulkan, GL is OpenGL, ARB is “Architecture Review Board” as its sort of a preview or extension feature I think. EXT presumably for extension. KHR is Khronos, the organization that creates the Vulkan and OpenGL standards, and the acronym apparently means it’s “Khronos-approved”. https://registry.khronos.org/vulkan/specs/1.1-extensions/html/vkspec.html#extensions
Most of the lowercase abbreviations are just the names of device drivers or platforms. VK is just Vulkan, GL is OpenGL, ARB is “Architecture Review Board” as its sort of a preview or extension feature I think. EXT presumably for extension. KHR is Khronos, the organization that creates the Vulkan and OpenGL standards, and the acronym apparently means it’s “Khronos-approved”. https://registry.khronos.org/vulkan/specs/1.1-extensions/html/vkspec.html#extensions