ProRender is a render engine created by AMD to use with their Radeon GPUs
ProRender is a render engine created by AMD to use with their Radeon GPUs. It can work with Blender, Maya, 3DMax, Unity, etc. The ProRender works similarly to Cycles, both of them use ray-tracing algorithm.
This render engine is especially useful for MacBook users because Apple doesn't support CUDA nor OpenCL so it's not possible to use GPU on MacBooks by default – and ProRender can fix this.
ProRender provides it's own material nodes for Blender, the most popular of them is
RPR Uber shader node for PBR (Physically Based Rendering). In addition, AMD provides Material Library which contains many materials ready to use with the ProRender.