How Computers Work - Key Terms (Pages 3–6)

Vocabulary flashcards covering key terms and definitions from Pages 3–6 on How Computers Work.

CPU (Central Processing Unit)

The main processor responsible for executing instructions and coordinating all computer operations; also called a microprocessor; composed of a Control Unit, Arithmetic Logic Unit, and registers.

Control Unit (CU)

Part of the CPU that controls and coordinates computer components, reads the next instruction, increments the program counter, and supplies data to the ALU or registers.

Arithmetic Logic Unit (ALU)

Performs all arithmetic calculations and logical operations (e.g., addition, subtraction, comparisons).

Registers

Tiny, fast storage inside the CPU that holds data or instructions to be executed next.

RAM (Random Access Memory)

Volatile, temporary memory that stores data for quick access by the processor; data can be read and written randomly.

ROM (Read-Only Memory)

Non-volatile, permanent storage that cannot be modified during normal operation; used to store firmware and essential instructions.

Primary Memory

The computer's main memory, including RAM and ROM, located close to the CPU.

Secondary Memory

Non-volatile storage that retains data when power is off; used for long-term storage; examples include hard drives, optical disks, and USB flash drives.

Hard Disk Drive

A magnetic secondary storage device used for long-term data storage.

Optical Disks (CD, DVD)

Secondary storage media that use optical technology for data storage.

USB Flash Drive

Portable flash memory device used for secondary storage.

Input Device

Peripheral that provides data and control signals to a computer; common examples are keyboards and mice; translates human input into a computer-readable form.

Output Device

Hardware that conveys processed information in a human-readable form; examples include monitors and printers.

Hardware

The physical components of a computer (tangible objects such as CPU, RAM, motherboard, keyboard, mouse, printer, wires, transistors, etc.).

Software

Computer programs and data; organized collections of instructions and information that a computer can execute.

Operating System Software

Software that manages hardware and software resources and provides common services for programs (examples: Windows, Mac OS X, Linux, Unix).

Application Software

Software designed to perform specific tasks for users (e.g., word processors, browsers) beyond basic system operation.