Shaders are programs that run on the GPU. That term, like all others, come from the graphics processing background and history of GPUs. Like the CPU, a GPU onl

Shaders are programs that run on the GPU. That term, like all others, come from the graphics processing background and history of GPUs. Like the CPU, a GPU only understands its own instruction set. If you want to run software on a GPU, you must write it in a language that can compile to that instruction set. Making interpreters that run arbitrary languages doesn‘t really work on GPUs. They aren’t general purpose processors, after all. Edit: researching GPU history might be helpful. In the old days, the era of early OpenGL and Direct3D, what you could do with a GPU was extremely limited. You could enable/disable some things and tweak some parameters, but what the GPU was really doing was out of your control. Google fixed function pipeline. In more recent times, with Shaders and especially with the newer standards / APIs like Vulkan, Direct3D12, Metal and now WegGPU, the GPUs internals have been made much more flexible and blown open. We now have much more low level control. GPUs are quite complicated, so naturally working with these low level APIs is also complicated.