Computer Science Review Topics 1 to 4

Comprehensive vocabulary flashcards covering System Design, Computer Organisation, Networks, and Computational Thinking / Programming.

Feasibility Study (TELOS)

An evaluation assessing Technical, Economic, Legal, Operational, and Schedule factors to determine whether a project is worth pursuing.

Technical Feasibility

The assessment of whether existing or available technology is sufficiently advanced to construct the proposed system.

Economic Feasibility

The assessment of whether the proposed system is cost-effective and whether sufficient financial funds are available.

Legal Feasibility

The assessment of whether the proposed system conflicts with any existing regulations, laws, or statutes.

Operational Feasibility

The assessment of whether current organizational structures and procedures are adequate to operate and support the new system.

Schedule Feasibility

The assessment of the time needed to implement the proposed system and whether that timeframe is acceptable.

Change Management

The process of guiding individuals, teams, and organizations from a current state to a target state, maximizing positive outcomes and minimizing disruptions to ensure stakeholder buy-in.

Legacy System

An outdated computer hardware or software system that continues in operation because it satisfies functional requirements, even though its data cannot easily be updated or migrated.

Locally Hosted System

A software deployment model where applications are installed and executed entirely on the client's own physical infrastructure.

Remotely Hosted System / SaaS

Software as a Service; a model where software executes on vendor-managed hardware and users access it via an internet connection on a subscription basis.

Parallel Changeover

An implementation strategy where the outgoing and incoming systems operate concurrently until the new system is verified as dependable.

Direct (Big Bang) Changeover

An implementation strategy where the existing system is decommissioned and the replacement system is activated simultaneously.

Pilot Changeover

An implementation approach where the new system is introduced to a single department or location first, followed by wider rollout once proven successful.

Phased Changeover

An implementation approach where the system is integrated step-by-step, activating individual components or departments successively.

Data Migration

The technical transfer of digital information across storage types, formats, or computational architectures during transitions or consolidations.

Alpha Testing

Preliminary software testing performed internally by development staff in a controlled setting prior to any release to external parties.

Beta Testing

Field testing conducted by target end-users outside the development organization to obtain practical feedback ahead of general distribution.

User Acceptance Testing (UAT)

Final verification conducted by intended clients or operators to validate that software satisfies business needs before formal sign-off.

Debugging

The organized approach of discovering, analyzing, and removing logic or syntax defects within software source code.

Static Testing

The process of verifying software quality by inspecting code, documentation, or specifications without executing the program.

Dynamic Testing

The process of validating a system by executing its compiled or interpreted code against predetermined test data.

Automated Testing

The practice of running software test suites and evaluating observed outputs against expected behaviors using automated software tools.

Failover System

A secondary backup infrastructure designed to automatically assume operational duties if the primary system suffers an outage.

Data Redundancy

The deliberate duplication of files, database entries, or physical devices so that hardware or software faults do not produce data loss.

Patch

A compact software modification designed to repair a specific security flaw or program fault.

Software Update

A software package that resolves defects and may provide subtle feature adjustments, typically provided at no additional cost.

Software Upgrade

A major new iteration of a software package that delivers substantial capability additions alongside bug resolutions, frequently requiring payment.

Release

A completely evaluated, deployment-ready build of a software application distributed for general use.

Hardware

The concrete, physical components comprising a computing device, including central processing units, keyboards, and internal storage devices.

Software

Collections of encoded computer instructions and data structures that direct hardware operations.

Peripheral Device

An auxiliary piece of hardware linked externally to a computer system to supply input, output, or storage functionality.

Human Resources

The personnel who operate, maintain, and interact with an organization's computer networks and computational tools.

Client

A network entity or piece of software that initiates service, file, or compute requests directed toward a host or server.

Server

A host system or application providing centralized network facilities, compute power, or data storage to requesting clients.

DNS Server

A specialized network server that maps alphanumeric human-readable domain designations to numerical IP addresses.

Router

A networking device that analyzes destination IP headers and routes packets across disparate networks.

Firewall

A hardware appliance or software layer that inspects and filters inbound and outbound data streams against defined security criteria.

Digital Divide

The socioeconomic inequality separating individuals with unrestricted access to modern computing technologies from those without.

Reliability

The consistency with which a computer hardware or software platform operates according to its technical parameters without unexpected breakdowns.

Data Integrity

The condition of digital information being correct, exhaustive, unified, and protected from unintended modifications.

Stakeholder

Any party who exerts influence on or experiences effects from a technical project, including developers, business executives, clients, and everyday users.

End-User

The actual human operator intended to interact directly with an implemented software or hardware solution.

System Flowchart

A schematic mapping the flow of physical and logical information through a system, depicting processes, storage modules, databases, and hardware units.

Data Flow Diagram (DFD)

A structural model illustrating the paths along which information travels, transforms, and rests within a system, independent of underlying hardware mechanisms.

Structure Chart

A graphical representation showing the top-down decomposition of a computer program into independent sub-routines and functional modules.

Prototype

A rudimentary preliminary model of a software application constructed with core features to evaluate assumptions and gather stakeholder reactions.

Iteration (Design)

A repetitive development cycle encompassing design, implementation, analysis, and appraisal to incrementally elevate system quality.

Usability

The degree of operational efficiency, subjective satisfaction, and task efficacy experienced by a human interacting with a digital interface.

Accessibility

The degree to which an IT product or service accommodates individuals spanning diverse physical or cognitive conditions, including those with disabilities.

CPU

Central Processing Unit; the primary computational component that continually fetches, parses, and executes encoded machine instructions.

Control Unit (CU)

The central processing core subsystem that regulates internal data pathways, retrieves instructions, and orchestrates functional executions.

Arithmetic Logic Unit (ALU)

The internal processing circuit of the CPU dedicated to executing mathematical calculations and Boolean operations.

Register

An extremely fast, small, hardware-level storage location integrated directly into the CPU architecture.

Memory Address Register (MAR)

A CPU register that stores the specific memory address targeted for an impending read or write cycle.

Memory Data Register (MDR)

A CPU register that holds the payload or operational instruction freshly retrieved from or queued for delivery to primary storage.

Accumulator

A CPU register designed to temporarily retain interim calculations and outputs generated by the Arithmetic Logic Unit.

Bus

A set of parallel electrical tracks or pathways used to transmit memory addresses, computational data, and control directives between system elements.

Machine Instruction Cycle

The repetitive four-stage processing loop wherein a CPU fetches an instruction from memory, decodes it via the CU, executes it via the ALU, and records the output.

Primary Memory

High-speed internal storage directly addressable by the CPU, consisting of RAM, ROM, and processor cache.

RAM

Random Access Memory; volatile read/write primary storage that holds active program code and working memory, which clears when disconnected from power.

ROM

Read-Only Memory; non-volatile storage containing static boot routines and firmware like the BIOS that cannot be readily modified or erased.

Cache Memory

High-speed intermediate memory positioned adjacent to or inside the CPU to store recurring instructions and minimize delays from accessing RAM.

Persistent Storage

Non-volatile secondary storage media such as SSDs, optical discs, and magnetic hard drives that preserve data permanently without sustained electrical supply.

Virtual Memory

An operating system mechanism that designates a portion of secondary disk storage to emulate physical RAM when operational memory runs out.

Operating System

Core system software responsible for allocating physical resources, supervising file hierarchies, enforcing security, and providing hardware abstraction to applications.

Bit

The most fundamental unit of digital computation, manifesting as an individual binary state of $0$ or $1$.

Byte

A contiguous sequence of $8$ bits capable of encoding $2^8 = 256$ distinct unsigned numeric states.

Binary

A base-$2$ numerical representation scheme utilizing exclusively the symbols $0$ and $1$.

Denary

A base-$10$ positional numbering format utilizing standard Arabic numerals spanning $0$ through $9$.

Hexadecimal

A base-$16$ notation system employing numerals $0$ through $9$ alongside alphabetical characters $A$ through $F$ ($A = 10$ through $F = 15$).

AND Gate

A fundamental logic gate that yields an output state of $1$ exclusively when all incoming inputs are configured to $1$.

OR Gate

A logic gate that yields an output state of $1$ whenever at least one applied input resolves to $1$.

NOT Gate

A single-input logic gate that outputs the logical inverse of the supplied electrical signal.

NAND Gate

A compound logic gate representing NOT-AND, producing an output of $0$ only when both input signals evaluate to $1$.

NOR Gate

A compound logic gate representing NOT-OR, producing an output of $1$ exclusively when all supplied inputs evaluate to $0$.

XOR Gate

An exclusive OR gate that delivers an output signal of $1$ only when its two input states are unequal.

Network

An infrastructure composed of interconnected compute nodes and devices configured to exchange information and utilize common resources.

Node

Any individual addressable physical terminal or device actively attached within a computing network topology.

Local Area Network (LAN)

A computer network spanning a restricted geographical footprint, such as a private home, school facility, or commercial workplace.

Wireless Local Area Network (WLAN)

A local area network configuration where terminals interact via high-frequency radio waves rather than physical copper or optical cables.

Virtual Local Area Network (VLAN)

A software-defined network segmentation architecture that isolates connected endpoints into logical subnets independently of their physical wiring.

Wide Area Network (WAN)

A communication network covering broad regional or national territories, bridging disparate local area networks together.

Storage Area Network (SAN)

A dedicated, high-speed data network designed to provide block-level storage consolidation and access to servers.

Personal Area Network (PAN)

A localized communication link operating within the immediate operational perimeter of a single individual, typically leveraging Bluetooth.

Peer-to-Peer (P2P) Network

A decentralized architecture wherein individual participating nodes carry equivalent operational status, behaving simultaneously as servers and clients.

Internet

A worldwide interconnection of disparate public and private networks operating over unified communication protocols to deliver web, email, and transfer capabilities.

Intranet

A private, secured digital network built using web standards, restricted exclusively to internal enterprise staff.

Extranet

A controlled extension of an internal corporate network granting partitioned, authenticated access to external stakeholders, suppliers, or partners.

Virtual Private Network (VPN)

An encrypted communication tunnel constructed across untrusted public networks to grant authenticated users secure entry into private networks.

Protocol

A formal framework of digital communication standards and syntax conventions regulating transmission across interconnected hardware.

Data Packet

A partitioned transmission block circulating over a network, composed of metadata headers, the primary payload, and error-verifying trailers.

Packet Switching

A transmission approach where messages are segmented into discrete packets routed across disparate paths and recompiled at the receiving node.

Flow Control

A network mechanism that balances transmission rates so a high-speed sender does not overrun the reception capacity of a slower receiver.

Deadlock

An execution condition wherein two competing operations remain indefinitely paused because each awaits exclusive resources held by the other.

Congestion Management

Protocols and policies established within network equipment to mitigate data path bottlenecks and prevent packet drops caused by excessive traffic.

Bandwidth

The theoretical maximum volume of digital data capable of traveling across a communication channel per second, quantified in bits per second.

Throughput

The measured real-world volume of valid data successfully carried across a network channel per unit of time.

Bottleneck

The point of narrowest capacity or lowest data processing rate along a network path, establishing the maximum overall throughput for transmission.

Lossy Compression

A data encoding method that achieves significant reduction in file footprint by permanently stripping non-essential data, preventing exact restoration.

Lossless Compression

A data reduction process that shrinks storage overhead without discarding any original bits, permitting complete and bit-for-bit reconstruction.