A platform is an abstraction for a window system, OS, etc. Some examples include MS Windows, Android, and Wayland. The Vulkan API may be integrated in a unique manner for each platform.
The Vulkan API does not define any type of platform object. Platform-specific WSI extensions are defined, which contain platform-specific functions for using WSI. Use of these extensions is guarded by preprocessor symbols.
In order for an application to be compiled to use WSI with a given platform,
it can #define the appropriate preprocessor symbol prior including the
"vulkan.h" header file. Each platform-specific extension is an instance
extension; and the application must enable instance extensions with
vkCreateInstance
before using them.