Complex Instruction Set Computer

computing

Also known as: CISC

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Last updated

July 23, 2026

Quick Summary

Complex Instruction Set Computer (CISC) is a type of microprocessor design that utilizes a large set of intricate instructions. This contrasts with Reduced Instruction Set Computer (RISC) designs, which employ simpler, faster instructions. CISC processors are designed to execute complex codes more efficiently because they have a more extensive built-in instruction set. This allows them to perform tasks with fewer lines of code compared to RISC processors, which need to break down complex instructions into simpler ones. While CISC dominated the personal computer market for a time, RISC technology has since been integrated into various devices, including smartphones.12

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RISC
In contrast, CISC chips have a large, complex resident instruction set. Therefore, they typically process complex codes more quickly. RISC chips must break the complicated code down into simpler units before they can execute it. Furthermore, software developed for use with RISC computer systems must provide a…
Read More
In contrast, CISC chips have a large, complex resident instruction set. Therefore, they typically process complex codes more quickly. RISC chips must break the complicated code down into simpler units before they can execute it. Furthermore, software developed for use with RISC computer systems must provide a…
Read More