Hardware and Computer Architecture

A comprehensive vocabulary review of computer hardware fundamentals, covering CPU architecture, memory types, registers, buses, peripheral devices, secondary storage, and embedded systems.

Central Processing Unit (CPU)

The component that processes data and instructions (millions per second), performing simple arithmetic calculations and logical comparisons.

Clock Speed

A measurement of CPU speed; the faster it is, the faster the computer can run the fetch-decode-execute cycle and process more instructions.

Multi-core Processor

A CPU containing multiple processing components within the same unit, enabling simultaneous processing of instructions (such as two instructions at once in a dual-core CPU).

Controller

A CPU component that sends and receives signals from all parts of the computer, ensuring all processes take place at the right time and in the correct order.

Arithmetic and Logic Unit (ALU)

The part of the CPU that processes and manipulates data by performing simple calculations and comparisons on data temporarily stored in registers.

Registers

Temporary storage locations found on the CPU that hold data or control information, accessible much faster than internal memory.

Internal Memory (Level 1 cache)

Fast-access temporary storage on the CPU where data is moved from the registers when it is not being actively used.

CPU Architecture

A term referring to the design of a microprocessor, which is an integrated circuit.

Von Neumann Architecture

A CPU design where the program and the data are stored in the same memory space, making it easier to re-program.

Von Neumann Bottleneck

A limitation in Von Neumann architecture where an instruction fetch and a data operation cannot occur simultaneously because they share a common bus.

Harvard Architecture

A CPU design where program memory and data memory each have their own dedicated bus.

Address Bus

A bus along which the storage address of data travels whenever data is saved to or loaded from memory.

Data Bus

The physical pathway along which data travels when moved between different parts of a computer.

Control Bus

A bus used specifically by the controller to transmit control signals to different parts of the computer.

Volatile Memory

A type of memory where stored data is lost when power is switched off.

Non-volatile Memory

A type of memory that continues to retain and store data even when it has no power.

Random Access Memory (RAM)

Volatile memory used for the temporary storage of currently running programs and data.

Read Only Memory (ROM)

Non-volatile memory used for the permanent storage of data, such as the BIOS.

Flash Memory

Non-volatile memory used for the permanent storage of data where the stored data can still be altered.

Virtual Memory

Temporary memory allocated on a secondary storage drive (hard drive) when a computer runs many processes simultaneously and RAM runs low.

Cache Memory

Temporary storage of frequently accessed data and instructions consisting of a small number of memory locations that can be accessed by the CPU much faster than RAM.

Fetch

The step in the instruction cycle that retrieves the instruction address from memory, stores it in the instruction register, and increments the program counter by one to point to the next instruction.

Decode

The step in the instruction cycle where the control unit analyzes the instruction in the instruction register to determine the required action.

Execute

The step in the instruction cycle where the actual actions defined by the instruction are carried out.

Program Counter (PC)

A register that stores the memory location of the next instruction required by the processor.

Current Instruction Register (CIR)

A register that stores the instruction currently being executed by the processor.

Accumulator (ACC)

A register that stores the results of calculations performed by the ALU.

Memory Address Register (MAR)

A register that holds the memory location where data is currently being written to or read from.

Memory Data Register (MDR)

A register that holds data while it is being transferred from memory to the CPU or vice versa.

Input Device

A hardware device that allows data, such as text, images, video, or sound, to be entered into a computer system.

Output Device

A hardware device that allows processed data, such as text, images, video, or sound, to come out of a computer system.

Secondary Storage

Non-volatile backing storage where data is transferred from memory when no longer actively used, allowing retrieval at a later time.

Optical Storage

Storage media (such as CDs, DVDs, and Blu-Ray discs) that are read and written using lasers.

Magnetic Storage

Storage media (such as magnetic disks or tapes) where data is stored magnetically using a read-head and write-head.

Solid State Storage

Storage media without moving parts, featuring low power consumption and high-speed data access.

Motherboard

The primary circuit board of a computer where components like the CPU and ROM are mounted, featuring expansion slots and USB ports.

Graphics Processor Unit (GPU)

A specialized microprocessor that carries out calculations required to display graphic images on screen and process complex visuals rapidly.

Integrated GPU

A graphics processor that shares the computer's system RAM, offering lower cost and reduced heat production for general tasks like word processing and video viewing.

Dedicated GPU

A graphics card equipped with its own video memory that provides superior visual performance for gaming and design, at the cost of higher power consumption and greater cooling demands.

Sound Card

A hardware device located on the motherboard or installed into a PCI slot that enables a computer to produce audio output.

Embedded System

A dedicated combination of computer hardware and software engineered to execute a single specific task, often integrated inside a larger mechanical device.

Firmware

The specialized software written specifically for an embedded system.

Optical Mark Reader (OMR)

An input device that reads pre-designed forms containing marked multiple-choice choices, such as on lottery tickets.

Optical Character Recognition (OCR)

Software technology that converts printed or typed text into editable digital documents through shape-based pattern matching.

Magnetic Ink Character Recognition (MICR)

An input technology that reads characters printed with magnetized ink, commonly found at the bottom of bank cheques.

Byte (B)

A digital storage unit consisting of $8$ bits.

Kilobyte (KB)

A digital storage unit equal to $1024$ bytes.

Megabyte (MB)

A digital storage unit equal to $1024\text{ KB}$.

Gigabyte (GB)

A digital storage unit equal to $1024\text{ MB}$.

Terabyte (TB)

A digital storage unit equal to $1024\text{ GB}$.