This document summarizes key aspects of computer organization from the 10th edition of the textbook "Computer Organization and Architecture" by William Stallings. It discusses the hierarchical structure of computers, with the CPU controlling four basic functions: data processing, storage, movement, and control. The CPU contains an ALU, registers, and a control unit. Modern computers often have multiple processing cores on a single chip. Cache memory enhances performance by storing frequently used data closer to the processor cores. The document traces the evolution of computer architecture from the first generation of vacuum tube computers to modern multicore designs.