In computer engineering, micro-architecture, also called computer organization, is the way a given instruction set architecture (ISA) is implemented on a processor. A given ISA may be implemented with different micro-architectures. Implementations might vary due to different goals of a given design or due to shifts in technology. Computer architecture is the combination of micro-architecture and instruction set design. The interaction between computer architecture and technology is examined. To evaluate the attractiveness of particular technologies, computer designs are assessed primarily on the basis of performance and cost. The technology trends discussed concern memory size, design complexity and time, and design scaling. Opportunities and problems to be solved in the years ahead are identified.