RISC-V is an open standard instruction set architecture (ISA), which is quickly gaining popularity and is now a viable alternative for ARM, certainly in low power applications, such as Edge computing and IoT.
The benefit of the RISC-V open standard is that companies implementing processors on their SoCs have much more freedom to decide whether they develop in-house, use open source, or buy proprietary cores, and have a much wider range of support/service models and possibilities for customizations than is the case in other ISA eco-systems. RISC-V has reduced significantly the problem of 'Vendor lock-in', and open-source implementations have even eliminated this process completely.