Complex Instruction Set Architecture (CISC) : The CISC approach attempts to minimize the number of instructions per program, sacrificing the number of cycles per instruction.
Reduced Instruction Set Architecture (RISC): RISC does the opposite, reducing the cycles per instruction at the cost of the number of instructions per program.
In Modern computer, RISC architecture is preferable since memory is not much expensive. In RISC architecture your program size is more and fast processing.
Please correct me if I am wrong.