The AMD-K6 family of processors are based on a sophisticated RISC core known as the Enhanced RISC86 microarchitecture. The Enhanced RISC86 microarchitecture is an advanced, second-order decoupled decode/execution design approach that enables industry-leading performance for x86-based software.
The term design implementation refers to the actual logic and circuit designs from which the processor is created according to the microarchitecture specifications.