Past and future of hardware and architecture

RISC-V ("RISC Five") is the proposed free and open champion, which has a small base of classic RISC instructions that run a full open-source software stack; opcodes reserved for tailoring an System-On-a-Chip to applications; standard instruction extensions optionally included in an SoC; and it is unrestricted: there is no cost, no paperwork, and anyone can use it.