Key terms bank

Key terms A to F

Abstraction: Hiding detail so only the essential features are shown.
Acceptance testing: Client/users check the system meets their needs.
Accountability: Actions are traceable to a person (logs).
Actuator: Output device that moves or acts (motor, hydraulic actuator).
Adaptive maintenance: Changing software for a new environment.
Agile: Iterative approach with short sprints and continuous feedback.
AI: Machines performing tasks that need human intelligence; ML is a subset.
API: Rules letting software components request data or services from each other.
Asymmetric encryption: Public key encrypts, private key decrypts.
Authentication: Proving who you are.
Authorisation: Deciding what you may do.
Availability: Systems and data are accessible when needed.
Backtracking: Try an option, retreat on a dead end, try another.
Beta testing: Real users trial a near-final version.
Bias (human, dataset): Unfair skew in data, labels or decisions that favours some outcomes or groups.
Big data: Huge, fast, varied data sets.
Boundary testing: Test at and either side of the limits.
BPA: Business process automation of whole workflows.
Breakpoint: Pauses execution at a chosen line.
Business continuity: Keeping critical operations running through disruption.
Cipher text: Encrypted, unreadable data. Plain text: readable data.
Class: Blueprint for objects.
CMS: Content management system (WordPress, Drupal, Joomla).
Code review: People read code to find flaws.
Confidentiality: Only authorised people can read data.
Corrective maintenance: Fixing bugs after release.
CRUD: Create, Read, Update, Delete (INSERT, SELECT, UPDATE, DELETE).
CSRF: Cross-site request forgery: forged request using a logged-in user's trust.
CSS: Cascading Style Sheets: presentation of web pages.
DAST: Dynamic application security testing of the running app.
Data dictionary: Table describing every variable (type, format, size, description, example, validation).
Data mining: Finding patterns in large data sets.
Data packet: Chunk of data with header and payload.
Decision tree: Diagram of decisions and resulting actions (also an ML model).
DevOps: Development plus operations: CI/CD, rapid feedback, automation, shared ownership.
DFD: Data flow diagram.
Digital signature: Hash encrypted with sender's private key; proves origin and integrity.
Direct implementation: Old system off, new on at once.
Disaster recovery: Restoring systems and data after a major incident (RTO, RPO).
DNS: Domain name system: name to IP address (port 53).
Driver: Test code that calls a module under test.
Encapsulation: Data and methods bundled and protected.
Exception management: Handling runtime errors without crashing (try/except).
Feasibility: Whether a project is achievable (schedule, financial).
FTP / SFTP: File transfer (port 21) / secure file transfer over SSH (port 22).
Functional requirement: What the system must do.

Key terms G to P

Gantt chart: Tasks against time with dependencies and milestones.
Generalisation: Common features pulled up into a superclass.
GDPR: EU General Data Protection Regulation.
Hardening: Reducing attack surface through configuration and patching.
Hash value: Fixed-length output of a one-way function.
HTTP / HTTPS: Web protocol (port 80) / encrypted version (port 443).
IMAP / POP3 / SMTP: Email: sync on server (143) / download (110) / send (25).
Inheritance: Subclass reuses and extends a superclass.
Input validation: Checking input meets rules before use.
Integrity: Data accurate and unchanged by unauthorised parties.
IPv4: 32-bit address written as four numbers 0-255.
K-nearest neighbour: Classify by the majority of the K closest points.
Language-dependent optimisation: Efficiency gains using features of a specific language.
Lazy loading: Load media only when needed.
Linear regression: Predicts a continuous numeric value on a straight line.
Logbook / process diary: Dated record of progress, issues and reflections.
Logistic regression: Classification (yes/no) using probability.
Machine learning: Algorithms that learn patterns from data.
Metadata: Data about data.
Minification: Removing unnecessary characters from code to reduce file size.
MLOps: Design, model development and operations stages for ML.
Neural network: Layers of weighted nodes trained by backpropagation.
ORM: Object-relational mapping: database rows as objects.
Parallel implementation: Old and new run side by side.
Penetration testing: Authorised simulated attack that exploits weaknesses.
Perfective maintenance: Improving performance or features.
Phased implementation: New system introduced in stages.
Pilot implementation: New system trialled by a small group first.
Polymorphism: Same method name, different behaviour per class.
Privacy by design: Proactive not reactive; embed privacy into design; respect for user privacy.
Progressive web app (PWA): Installable, offline-capable web app (service worker, manifest, HTTPS).

Key terms Q to Z

Race condition: Outcome depends on the timing of concurrent access to shared data.
Regulatory compliance: Meeting laws, regulations and standards.
Reinforcement learning: Learn from rewards and penalties.
RPA: Robotic process automation: bots mimic user actions.
Sandboxing: Isolated environment that limits what code can do.
SAST: Static application security testing of source code without running it.
Sanitisation: Cleaning or encoding input to neutralise dangerous characters.
Security by design: Security built in from the start.
Semi-supervised learning: Few labels plus many unlabelled examples.
Sensor: Input device detecting the environment.
Service worker: Background script that caches and intercepts requests.
Session management: Tracking a user's state across requests with a session ID.
Side-channel attack: Learning secrets from timing, power or electromagnetic leakage.
SQL injection: Malicious SQL inserted via input; stopped by parameterised queries.
SSL/TLS certificate: Proves a site's identity and enables HTTPS.
Stub: Placeholder for an unfinished module.
Supervised learning: Learn from labelled data.
Symmetric encryption: One shared key.
TCP/IP: Reliable delivery (TCP) and addressing/routing (IP).
Two's complement: Signed binary: invert bits and add 1.
Unsupervised learning: Find patterns in unlabelled data.
Version control: Tracks changes, branches, merges and reverts code.
Volume testing: Test with large amounts of data.
W3C / WAI: Web standards body / web accessibility initiative.
Waterfall: Sequential, plan-driven phases.
WAgile: Hybrid of Waterfall planning and Agile iteration.
Web manifest: JSON file with app name, icons and display mode.
XSS: Cross-site scripting: malicious script injected into a page other users view.

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