Computer Hardware, Architecture, and Storage Systems

Comprehensive vocabulary flashcards covering foundational computer hardware, the IPOS cycle, processor components, memory hierarchies, I/O operations, storage mechanics, RAID configurations, and Boolean logic.

Information Technology

The technology and people used in creating, maintaining, and making information available.

Computer

An electronic device for storing and processing data, typically in binary form based on instructions given to it in a variable program.

IT Infrastructure

The combined computer systems, networks, operating systems, and resources that support an organization.

Hardware

The physical components of a computer, such as the CPU, keyboard, and hard drive.

Software

The programs and instructions that tell a computer what to do.

Moore's Law

The observation that the number of transistors on an integrated circuit doubles approximately every $2$ years, leading to exponential growth in computing power and declining cost per transistor.

Bit

A single binary digit with a value of either $0$ or $1$.

Byte

A sequence of $8$ bits capable of representing $256$ different values (from $0$ to $255$), commonly used to store characters.

Volatile Memory

Computer memory that loses its stored contents when electrical power is removed.

Nonvolatile Memory

Computer memory or storage that retains its contents without electrical power.

Peripheral

An auxiliary input, output, or other external device connected to a computer system.

General-Purpose Computer

A computer designed to be capable of running many different programs and tasks.

IPOS Cycle

The fundamental four-stage computing process consisting of Input (data enters), Processing (data is transformed), Output (results are presented), and Storage (data is saved).

System Administrator

An IT professional who maintains computer systems, software configurations, user accounts, and system security.

Network Administrator

An IT professional responsible for setting up, maintaining, and troubleshooting computer networks.

Database Administrator

An IT professional who manages and maintains databases, controls user access permissions, and handles data backups.

Motherboard

The primary printed circuit board that connects and facilitates communication among all major computer components.

Central Processing Unit (CPU)

The primary processor of a computer that executes machine instructions, coordinates data movements, and performs arithmetic and logical operations.

Control Unit (CU)

The internal component of the CPU that acts like a conductor by fetching instructions, decoding opcodes and operands, regulating timing, and issuing control signals to registers, ALU, memory, and I/O.

Arithmetic Logic Unit (ALU)

The execution component of the CPU that performs arithmetic (+, -, ×, ÷), logical comparisons (=, >, <), bit shifts, and Boolean operations.

Registers

The fastest, smallest-capacity storage locations located directly inside the CPU that hold immediate operands, memory addresses, and execution state.

Cache Memory

Extremely fast, small memory located on or close to the processor cores that stores copies of recently or frequently used data and instructions to avoid slower main memory accesses.

Cache Hit

An event occurring when the processor finds the required instruction or data directly in cache memory, avoiding high-latency RAM access.

Cache Miss

An event occurring when the requested instruction or data is not present in cache memory, forcing the CPU to fetch it from slower system RAM.

RAM (Random Access Memory)

Fast, volatile working memory directly accessed by the CPU to hold programs and data currently in active use.

ROM (Read-Only Memory)

Nonvolatile memory retaining its data without power that stores permanent startup code and firmware.

BIOS

Firmware stored on a nonvolatile ROM chip that initializes and tests hardware components during system startup.

Instruction Cycle

The continuous four-stage execution sequence performed by the CPU: Fetch (get instruction from memory), Decode (determine instruction meaning), Execute (carry out operations), and Store (save results/state).

Clock Speed

The operational frequency of a processor measured in hertz (cycles per second), typically expressed in gigahertz ($\text{GHz}$), indicating billions of cycles per second.

Core

An independent CPU execution unit placed on a chip; multi-core processors place multiple cores on a single chip to execute instruction streams concurrently when tasks can be parallelized.

Virtual Memory

A memory management technique where the memory management unit (MMU) translates program virtual addresses to physical RAM addresses, providing process isolation and using secondary storage as supplemental memory when RAM is scarce.

Memory Hierarchy

The pyramid architecture of computer storage organizing memory from fastest, smallest, and highest-cost (registers, CPU cache) to slower, larger, and cheaper tiers (RAM, SSD/storage, network/archive).

Instruction Set Architecture (ISA)

The formal specification and contract between software and processor that defines supported machine instructions, registers, data types, and addressing modes.

Microarchitecture

The specific internal hardware design and physical implementation of an Instruction Set Architecture (ISA).

Word

The natural unit and data size that a computer processor handles efficiently in a single operation, commonly $32\text{-bit}$ or $64\text{-bit}$.

Synchronous I/O

An input/output communication method where the requesting process must pause and wait for data transfer to complete before executing subsequent operations.

Asynchronous I/O

An input/output method where data transfer is requested while the system continues performing other tasks, handling the result once notified.

Interrupt

A hardware or software signal that alerts the CPU to temporarily halt its current tasks and return attention to handle an external event or I/O transmission.

Direct Memory Access (DMA)

A hardware feature that enables peripherals and applications to transfer data directly to and from system memory without continuous CPU intervention.

IOPS (Input/Output Operations Per Second)

A storage metric measuring the total number of individual read or write operations a storage device can complete within one second.

Throughput

The total volume or quantity of data successfully transferred, sent, or received across a storage or network medium within a specified unit of time.

Latency

The duration of time it takes before requested data begins to arrive, representing the initial response time or delay of an access operation.

IOPS vs. Throughput vs. Latency

Key performance dimensions where IOPS denotes operation frequency, throughput denotes volume per unit time, and latency denotes transfer or delivery delay.

Serial Transmission

A communication mode where bits travel sequentially one at a time over a single path or wire, used in modern standards like USB, PCIe, SATA, and Ethernet.

Parallel Transmission

A data transmission mode where multiple bits travel simultaneously across multiple parallel lines or wires.

Platter

A circular magnetic disk inside a hard disk drive that stores binary data patterns.

Spindle

The motorized central cylinder of a hard drive that rotates magnetic platters at high operational speeds, up to $15{,}000\,\text{rpm}$.

Read/Write Head

The magnetic sensor component suspended over a hard drive platter that reads and writes magnetic data patterns as the disk spins.

Actuator Arm

The mechanical component inside a hard drive that positions and sweeps the read/write heads across the spinning platters to specific tracks.

Hard Disk Drive Anatomy

The physical internal structure of an HDD including platters, spindle, actuator arm, read/write heads, actuator axis, and connectors.

Solid-State Drive (SSD)

A high-speed storage device that stores data persistently using nonvolatile NAND flash memory without moving mechanical parts.

RAID

Redundant Array of Independent Disks; a technique that combines multiple physical hard drives into a single logical storage entity to improve performance, redundancy, or both.

RAID 0 (Striping)

A RAID configuration that stripes data evenly across two or more disks for high read/write performance, offering no data protection or fault tolerance.

RAID 1 (Mirroring)

A RAID configuration that writes identical copies of data to two separate disks to provide high data redundancy and fault tolerance at the expense of storage efficiency.

RAID 5 (Striping with Parity)

A RAID configuration that stripes data and distributed parity across three or more disks, balancing speed, usable storage capacity, and fault tolerance.

RAID 10 (Mirrored Stripes)

A nested RAID configuration combining mirroring and striping (RAID $1+0$) across four or more drives to deliver the best overall performance and fault protection with lower storage efficiency.

Overview of Common RAID Levels

A comparison showing the trade-offs in speed, data protection, and storage capacity among RAID 0, RAID 1, RAID 5, and RAID 10.

Lossy Compression

A data compression technique that significantly reduces file size by permanently discarding certain non-critical information.

Parity Bit

An extra bit attached to a binary code string to detect single-bit transmission errors.

Two's Complement

A mathematical binary encoding system used by computers to represent and perform arithmetic with signed negative integers.

Boolean AND

A logical operation that evaluates to $1$ only when all evaluated input bits are $1$.

Boolean OR

A logical operation that evaluates to $1$ whenever at least one evaluated input bit is $1$.

Boolean XOR

A logical operation (exclusive OR) that outputs $1$ only when the compared input bits have different values.

Boolean NOT

A unary logical operation that reverses or inverts a bit, flipping $0$ to $1$ and $1$ to $0$.