55 Terms · AI · Web Development · SEO · Updated July 2026
Web Development, AI & SEO Glossary
Plain-language definitions of 55 terms across web development, artificial intelligence, and search engine optimisation. Every definition is written by the CV Infotech engineering team from direct experience building web applications, AI-integrated systems, and SEO-optimised sites for clients in the USA, UK, and Australia since 2012. Where a term relates to a service we provide, we link to the relevant page for more detail.
A
AI Agent
An AI agent is a software system that uses a large language model to plan and execute multi-step tasks autonomously, calling external tools — web search, code execution, API calls, file access — to complete goals that cannot be resolved from training knowledge alone. Agents differ from standard LLM completions in that they operate in loops: the model decides an action, executes it, observes the result, and decides the next action. Examples include coding agents, research agents, and customer support agents.
See also: AI Development Company
AI Hallucination
An AI hallucination is a confident but factually incorrect response generated by a large language model. Hallucinations occur because LLMs generate statistically plausible token sequences rather than retrieving verified facts. Mitigation strategies include retrieval-augmented generation (RAG), grounding responses in cited sources, and human review of AI-generated content in high-stakes contexts.
See also: AI Development Company
AI Overview
An AI Overview is a summary generated by Google's AI systems and displayed at the top of search results for certain queries, above the standard organic results. AI Overviews synthesise information from multiple web sources. Appearing in AI Overviews — or being cited by them — requires strong schema markup, authoritative content, and third-party citation coverage across the web.
See also: AI SEO Agency
AI SEO
AI SEO (also called AI-powered SEO or AEO — Answer Engine Optimisation) is the practice of optimising web content for visibility in AI-generated responses rather than exclusively for traditional search rankings. AI SEO techniques include implementing DefinedTermSet and FAQPage schema, building topical authority, creating content structured for direct extraction, and ensuring AI crawlers (GPTBot, ClaudeBot, PerplexityBot) are permitted in robots.txt.
See also: AI SEO Agency
AOT Compilation
AOT (Ahead-of-Time) compilation is an Angular build process that converts Angular HTML templates and TypeScript into efficient JavaScript code before the browser downloads and runs the application. AOT compilation catches template errors at build time rather than runtime, produces smaller bundle sizes by tree-shaking unused code, and results in faster application startup because the browser does not need to compile templates on first load.
See also: Angular Development Company
API-First Development
API-first development is a design approach in which the API contract — the defined endpoints, request structures, and response formats — is specified and agreed before any implementation begins. This enables frontend and backend teams to develop simultaneously against the agreed contract, and ensures the API is usable by multiple consumers (web app, mobile app, third-party integrations) rather than being designed around a single frontend's requirements.
See also: Web Development
B
BullMQ
BullMQ is a Node.js job queue library built on Redis that manages background job processing — tasks that run outside the main request cycle, such as sending emails, processing images, or generating reports. BullMQ provides retry policies, dead letter queues for failed jobs, concurrency controls, delayed jobs, and Bull Board for queue monitoring. It is the standard background job solution for Node.js applications requiring reliable task processing.
See also: Node.js Development Company
C
Canonical URL
A canonical URL is the preferred version of a web page when multiple URLs display identical or very similar content. The canonical is specified using a <link rel='canonical' href='...'> tag in the page's HTML head. Search engines consolidate ranking signals to the canonical URL, preventing duplicate content from splitting authority across multiple versions of the same page. Canonical tags are essential for eCommerce stores with faceted navigation and sites with both www and non-www versions.
See also: AI SEO Agency
CI/CD
CI/CD stands for Continuous Integration and Continuous Deployment. Continuous Integration is the practice of automatically building and testing code on every commit to a shared repository, catching integration errors early. Continuous Deployment extends this by automatically deploying passing builds to production or staging environments. CI/CD pipelines typically run linting, type checking, unit tests, and build verification on every pull request before code is merged.
See also: SaaS Development Company
CLS (Cumulative Layout Shift)
Cumulative Layout Shift (CLS) is a Core Web Vitals metric that measures visual instability — how much page elements unexpectedly shift position during loading. A CLS score below 0.1 is considered good. Common causes of high CLS include images without defined dimensions, late-loading fonts causing text reflow, and dynamically injected content above existing content. Google uses CLS as a search ranking signal.
See also: AI SEO Agency
Core Web Vitals
Core Web Vitals are Google's standardised metrics for measuring real-world user experience on web pages: Largest Contentful Paint (LCP) for loading performance, Cumulative Layout Shift (CLS) for visual stability, and Interaction to Next Paint (INP) for responsiveness to user input. Google incorporates Core Web Vitals into its search ranking algorithm. Tools for measuring Core Web Vitals include Google PageSpeed Insights, Lighthouse, and Search Console's Core Web Vitals report.
See also: AI SEO Agency
Crawl Budget
Crawl budget is the number of pages on a website that Google's crawler (Googlebot) will crawl within a given timeframe. Sites with large numbers of low-quality or duplicate pages can exhaust their crawl budget before important pages are crawled and indexed. Crawl budget is managed by returning correct HTTP status codes, disallowing unimportant URLs in robots.txt, and consolidating duplicate content with canonical tags.
See also: AI SEO Agency
D
DefinedTermSet
DefinedTermSet is a schema.org type for a structured collection of defined terms, each represented as a DefinedTerm. Implementing DefinedTermSet schema on a glossary page tells search engines and AI systems that the page is an authoritative reference for the terms it defines. AI systems including ChatGPT, Perplexity, and Google AI Overviews are more likely to cite content with formal term definitions than equivalent prose.
See also: AI SEO Agency
Docker
Docker is a platform for packaging applications and their dependencies into containers — isolated, portable environments that run consistently across development, staging, and production. A Docker container includes the application code, runtime, libraries, and configuration needed to run the application, eliminating 'it works on my machine' environment discrepancies. Docker is the standard deployment unit for modern web applications deployed to Kubernetes, AWS ECS, or cloud app platforms.
See also: SaaS Development Company
E
E-E-A-T
E-E-A-T stands for Experience, Expertise, Authoritativeness, and Trustworthiness — Google's framework for evaluating content quality in its Search Quality Evaluator Guidelines. Experience refers to first-hand knowledge of the topic. Expertise is demonstrated knowledge depth. Authoritativeness is recognition from other credible sources. Trustworthiness covers accuracy, transparency, and site security. E-E-A-T is particularly important for YMYL (Your Money or Your Life) content — health, finance, and legal topics.
See also: AI SEO Agency
esbuild
esbuild is a JavaScript and TypeScript bundler and minifier written in Go, designed for significantly faster build times than Webpack or Rollup. esbuild is used by Vite as its development server transformer and by Angular CLI from version 17 onwards as the production bundler. Build times that previously took 60 seconds with Webpack often complete in under 2 seconds with esbuild, improving developer feedback loops substantially.
See also: Angular Development Company
F
Fine-Tuning
Fine-tuning is the process of continuing to train a pre-trained large language model on a smaller, domain-specific dataset to adapt it to a particular task or domain. Fine-tuning adjusts the model's weights to improve performance on the target domain without training from scratch. A general-purpose LLM fine-tuned on medical literature will produce more accurate clinical summaries than the base model. Fine-tuning differs from RAG — fine-tuning modifies the model itself; RAG retrieves external context at inference time.
See also: AI Development Company
FHIR (HL7 FHIR)
HL7 FHIR (Fast Healthcare Interoperability Resources) is the current standard for health data exchange, now at version R4. FHIR defines a set of resources — standardised data structures for clinical concepts such as Patient, Observation, Condition, and MedicationRequest — and a REST API pattern for accessing them. FHIR R4 is mandated by the CMS Interoperability and Patient Access Rule for US healthcare providers and is the integration standard for NHS Digital in the UK.
See also: Healthcare Software Development
G
GEO (Generative Engine Optimisation)
Generative engine optimisation (GEO) is the practice of optimising web content for visibility in AI-generated responses — from ChatGPT, Perplexity, Google AI Overviews, Claude, and similar systems. GEO strategies include implementing DefinedTermSet and FAQPage schema markup, creating authoritative glossary and definition content, building third-party citations on high-authority platforms (Clutch, Crunchbase, G2), and ensuring AI crawlers are explicitly permitted in robots.txt. GEO is distinct from traditional SEO in that the 'search result' is a generated answer rather than a ranked list of links.
See also: AI SEO Agency
GraphQL
GraphQL is a query language and runtime for APIs developed by Meta and open-sourced in 2015. Unlike REST APIs where the server defines the response structure, GraphQL allows API consumers to specify exactly which data fields they need in a single request. This eliminates over-fetching (receiving unnecessary data) and under-fetching (requiring multiple requests for related data). GraphQL is particularly suited to applications with complex, nested data requirements and multiple client types with different data needs.
See also: Node.js Development Company
H
Headless CMS
A headless CMS (Content Management System) separates the content repository and editing interface from the presentation layer. Content is stored in the CMS and delivered via API to any frontend — a Next.js website, a React Native mobile app, a digital signage display. This separation allows the same content to appear across multiple channels without duplication. Popular headless CMS platforms include Contentful, Sanity, Strapi, and Prismic.
See also: Web Development
HIPAA
HIPAA (Health Insurance Portability and Accountability Act) is US federal law that governs how Protected Health Information (PHI) is stored, transmitted, and accessed by healthcare providers, health insurers, and their technology partners (Business Associates). HIPAA's Security Rule mandates specific technical safeguards: encryption at rest and in transit, access controls, audit logging, and automatic session logoff. Any software that handles PHI must be architected to meet HIPAA's technical requirements before launch.
See also: Healthcare Software Development
hreflang
The hreflang attribute is an HTML and XML sitemap annotation that tells search engines which language and regional version of a page to serve to users in different locations. For example, a site with English content for US and UK audiences uses hreflang='en-us' and hreflang='en-gb' tags to signal which version should appear in each country's search results. Incorrect hreflang implementation — missing x-default values or broken bidirectional links — is a common cause of international SEO problems.
See also: AI SEO Agency
I
INP (Interaction to Next Paint)
Interaction to Next Paint (INP) is a Core Web Vitals metric introduced as a replacement for First Input Delay (FID) in March 2024. INP measures the responsiveness of a page to all user interactions — clicks, taps, and keyboard inputs — throughout the entire page lifecycle, not just the first interaction. An INP below 200 milliseconds is considered good. Long JavaScript tasks on the main thread are the primary cause of poor INP scores.
See also: AI SEO Agency
ISR (Incremental Static Regeneration)
Incremental Static Regeneration (ISR) is a Next.js rendering strategy that regenerates static pages in the background after deployment, allowing them to be updated without a full rebuild. A page with ISR is served from the static cache on first request, then regenerated after a specified revalidation period. ISR combines the performance of static generation with the freshness of server-side rendering, making it suitable for product pages, blog posts, and content that changes regularly but not on every request.
See also: React Development Company
J
JAMstack
JAMstack is a web architecture based on JavaScript, APIs, and Markup — serving pre-built static HTML from a CDN rather than rendering pages on a server per request. The term was coined by Netlify's Mathias Biilmann in 2015. JAMstack sites offer high performance, strong security (no server-side code to exploit), and easy scaling. Modern JAMstack frameworks include Next.js, Gatsby, and Astro. JAMstack has largely superseded the term with 'static site generation' (SSG) for the underlying rendering strategy.
See also: React Development Company
K
Kubernetes
Kubernetes (K8s) is an open-source container orchestration system for automating the deployment, scaling, and management of containerised applications. Kubernetes manages clusters of machines running Docker containers, handling service discovery, load balancing, rolling deployments, and automatic restarts of failed containers. Kubernetes is the standard infrastructure platform for large-scale production applications and is available as a managed service from all major cloud providers (AWS EKS, Google GKE, Azure AKS).
See also: SaaS Development Company
L
Laravel
Laravel is a PHP web application framework known for its elegant syntax, comprehensive toolset, and strong conventions. Laravel provides routing, ORM (Eloquent), authentication, job queues, email, and testing out of the box. Its ecosystem includes Forge (server provisioning), Vapor (serverless deployment), Livewire (full-stack components), and Filament (admin panels). Laravel is the dominant PHP framework for new web application development and is used by CV Infotech for complex backend systems and client portals.
See also: Laravel Development Company
LCP (Largest Contentful Paint)
Largest Contentful Paint (LCP) is a Core Web Vitals metric that measures the time from when a page starts loading to when the largest visible content element — typically a hero image or headline — is rendered in the viewport. An LCP below 2.5 seconds is considered good. Common causes of poor LCP include unoptimised hero images, render-blocking JavaScript, slow server response times, and resources loaded without preloading.
See also: AI SEO Agency
LLM (Large Language Model)
A large language model (LLM) is a neural network trained on large volumes of text data to predict the next token in a sequence. Modern LLMs — including GPT-4o, Claude 3.5, Gemini 1.5, and Llama 3 — contain billions of parameters and can generate coherent text, answer questions, write and debug code, and perform multi-step reasoning. LLMs are the foundation of AI assistants, AI coding tools, and AI-powered search. They are probabilistic systems — they generate statistically plausible responses rather than retrieving verified facts.
See also: AI Development Company
llms.txt
llms.txt is a proposed standard file (analogous to robots.txt) placed at the root of a website to help AI systems understand and navigate the site's content. It typically contains a summary of the site's purpose, a list of key pages with descriptions, and links to the most important content. The file is read by AI crawlers and indexers to improve how AI-generated responses represent the site's content. CV Infotech's llms.txt is available at https://www.cvinfotech.com/llms.txt.
See also: AI SEO Agency
M
Microservices
Microservices is a software architecture pattern in which an application is decomposed into small, independently deployable services, each responsible for a distinct business capability and communicating with other services via APIs or message queues. Microservices offer independent scaling, independent deployment, and technology heterogeneity — each service can use the appropriate language and data store for its task. The trade-off is operational complexity: a microservices system requires service discovery, distributed tracing, and more sophisticated deployment infrastructure than a monolith.
See also: SaaS Development Company
Monorepo
A monorepo is a single version control repository containing the code for multiple projects or packages — for example, a frontend application, a backend API, and a shared component library all in one repository. Monorepos simplify dependency management between related projects and make atomic changes across multiple packages straightforward. Popular monorepo tools include Turborepo, Nx, and pnpm workspaces. The alternative — separate repositories per project — is called a polyrepo.
See also: SaaS Development Company
Multimodal AI
Multimodal AI refers to AI systems that process and generate multiple types of data — text, images, audio, and video — within a single model rather than specialised models for each modality. GPT-4o and Gemini 1.5 are examples of multimodal LLMs that can accept image inputs alongside text prompts. Multimodal capabilities enable applications such as visual question answering, image description, document analysis, and code generation from screenshots.
See also: AI Development Company
N
NgRx
NgRx is a state management library for Angular applications based on the Redux pattern — a single immutable store, actions that describe state changes, reducers that apply those changes, selectors for computing derived state, and effects for handling side effects such as API calls. NgRx provides time-travel debugging via Redux DevTools, strict action typing, and a predictable data flow that scales with application complexity. NgRx is appropriate for large Angular applications with complex shared state — it adds significant boilerplate for simple cases where a service with BehaviorSubject is sufficient.
See also: Angular Development Company
Node.js Event Loop
The Node.js event loop is the mechanism that enables Node.js to perform non-blocking I/O on a single thread. When an I/O operation (database query, HTTP request, file read) is initiated, Node.js registers a callback and continues executing other code. When the I/O completes, the callback is placed on the event queue and executed when the call stack is clear. This model enables Node.js to handle thousands of concurrent I/O-bound requests without the per-thread memory overhead of blocking server architectures.
See also: Node.js Development Company
O
OpenAPI
OpenAPI (formerly Swagger) is a specification for describing REST APIs in a machine-readable format (JSON or YAML). An OpenAPI document defines every API endpoint, the expected request structure, the possible response structures, and the authentication method. From an OpenAPI specification, tools can automatically generate interactive documentation (Swagger UI, Redoc), client SDKs, server stubs, and Postman collections. OpenAPI 3.0 and 3.1 are the current major versions.
See also: Node.js Development Company
P
Prisma
Prisma is a Node.js and TypeScript ORM (Object-Relational Mapper) that provides a type-safe database client generated from a schema definition. The Prisma schema defines data models, relationships, and database configuration. Prisma Client — generated from the schema — provides fully typed query methods, so database query results have known TypeScript types rather than being inferred at runtime. Prisma also includes a migration system for managing database schema changes. It supports PostgreSQL, MySQL, SQLite, MongoDB, and CockroachDB.
See also: Node.js Development Company
Progressive Web App (PWA)
A progressive web app (PWA) is a web application built using standard web technologies that provides capabilities traditionally associated with native mobile apps: offline functionality via service workers, push notifications via the Web Push API, and installation to the device home screen via the Web App Manifest. PWAs run in the browser and do not require App Store or Google Play distribution, reducing friction for users and eliminating platform distribution fees. Angular, React, and Next.js all support PWA development.
See also: Mobile App Development
Prompt Engineering
Prompt engineering is the practice of designing input prompts to elicit desired outputs from large language models. Effective prompt engineering techniques include providing clear context and role definitions, giving positive and negative examples (few-shot prompting), requesting step-by-step reasoning (chain-of-thought prompting), specifying the desired output format, and using XML or other structured delimiters to separate instructions from content. Prompt engineering is a practical skill for building AI-powered applications.
See also: AI Development Company
R
RAG (Retrieval-Augmented Generation)
Retrieval-Augmented Generation (RAG) is a technique for improving LLM outputs by retrieving relevant documents from an external knowledge base at inference time and including them in the prompt as context. The model generates its response using both its training knowledge and the retrieved context. RAG reduces hallucination by grounding responses in retrieved sources, enables responses about information not in the model's training data, and allows knowledge bases to be updated without retraining the model. RAG systems typically use a vector database for semantic similarity search.
See also: AI Development Company
REST API
A REST API (Representational State Transfer Application Programming Interface) is a web API that follows a set of architectural constraints: resources are identified by URLs, interactions use standard HTTP methods (GET, POST, PUT, PATCH, DELETE), responses are stateless (the server does not store client session state between requests), and representations are returned in a standard format (typically JSON). REST is the dominant API architectural style for web services, valued for its simplicity, wide tooling support, and compatibility with HTTP caching infrastructure.
See also: Node.js Development Company
Rich Results
Rich results are enhanced search result displays in Google Search that go beyond the standard title, URL, and description — including star ratings, FAQ dropdowns, product prices, event details, how-to steps, and breadcrumb trails. Rich results are enabled by implementing the corresponding schema.org structured data on the relevant pages. Google's Rich Results Test tool validates whether a page's structured data is eligible for rich result display.
See also: AI SEO Agency
RxJS
RxJS (Reactive Extensions for JavaScript) is a library for composing asynchronous and event-based programs using Observable sequences. In Angular, RxJS is the foundation of the HttpClient (which returns Observables), reactive forms, and router events. Key RxJS operators include switchMap (for cancellable requests), combineLatest (for state derived from multiple streams), shareReplay (for multicasting expensive operations), and takeUntilDestroyed (for preventing memory leaks when components are destroyed).
See also: Angular Development Company
S
Schema Markup
Schema markup (also called structured data) is code — typically JSON-LD embedded in a <script> tag — that uses vocabulary from schema.org to describe a web page's content in a way that machines can interpret. Common schema types include Organization, Product, FAQPage, Article, LegalService, Person, and DefinedTermSet. Search engines use schema markup to generate rich results and knowledge panel entries. AI systems use it to extract structured information for citation and question answering.
See also: AI SEO Agency
Search Intent
Search intent (also called query intent or user intent) is the underlying goal a user has when typing a search query. The four primary intent categories are: informational (seeking information — 'what is GraphQL'), navigational (seeking a specific site — 'cvinfotech contact'), commercial (researching before purchase — 'best Node.js development company india'), and transactional (ready to take action — 'hire node js developers'). Matching page content to the correct search intent is the most fundamental on-page SEO requirement.
See also: AI SEO Agency
SPA (Single-Page Application)
A single-page application (SPA) is a web application that loads a single HTML page and dynamically updates the content as the user interacts with it, without full page reloads. SPAs use JavaScript frameworks — React, Angular, Vue — to render content in the browser and communicate with backend APIs for data. SPAs provide a fast, app-like user experience after the initial JavaScript bundle loads, but require careful handling of SEO (search engines must be able to crawl JavaScript-rendered content) and initial load performance.
See also: Angular Development Company
SSG (Static Site Generation)
Static site generation (SSG) is a rendering strategy in which all pages are pre-rendered to HTML at build time and served from a CDN without a server. SSG produces the fastest possible page load times because there is no server computation on request — the HTML is ready to serve from the nearest CDN edge. It is appropriate for content that does not change per user or per request — marketing pages, documentation, blogs, and portfolio sites. Next.js, Gatsby, and Astro all support SSG.
See also: React Development Company
SSR (Server-Side Rendering)
Server-side rendering (SSR) is a rendering strategy in which HTML is generated on the server for each request and sent to the browser ready to display, before any JavaScript executes. SSR improves initial page load performance and search engine crawlability compared to client-side rendered SPAs. The trade-off is server compute cost per request and the complexity of managing server state. Next.js, Angular Universal, and Nuxt all support SSR alongside static generation.
See also: React Development Company
Structured Data
Structured data is information presented in a standardised, machine-readable format — as opposed to unstructured data like prose. On the web, structured data typically refers to schema.org vocabulary implemented as JSON-LD, used to annotate web pages with semantic meaning that search engines and AI systems can interpret. Common structured data formats include JSON-LD (the Google-recommended format), Microdata, and RDFa. Structured data enables rich results in search and improves AI citation accuracy.
See also: AI SEO Agency
T
TypeScript
TypeScript is a strongly-typed superset of JavaScript developed by Microsoft that compiles to plain JavaScript. TypeScript adds a static type system to JavaScript — catching type errors at build time rather than runtime — while remaining fully compatible with existing JavaScript code. TypeScript strict mode enables the most rigorous type checking: no implicit any types, strict null checks, and no unsafe type assertions. TypeScript is the standard language for professional React, Angular, Node.js, and Next.js development.
See also: React Development Company
V
Vector Database
A vector database stores and queries data as high-dimensional numerical vectors — mathematical representations of the semantic meaning of text, images, or other content. Vector databases enable similarity search: finding the most semantically similar items to a query rather than exact keyword matches. They are the standard data store for RAG (Retrieval-Augmented Generation) systems, where relevant documents are retrieved by semantic similarity to a user's query and included as context in an LLM prompt. Popular vector databases include Pinecone, Weaviate, Qdrant, and pgvector (a PostgreSQL extension).
See also: AI Development Company
Vibe Coding
Vibe coding is a software development approach in which the developer describes desired behaviour in natural language — the 'vibe' of what they want — and an AI coding tool (Cursor, GitHub Copilot, Claude, or a specialised tool like Bolt or Lovable) generates the corresponding code. The developer iterates by continuing to describe what they want rather than writing code directly. The term was coined by Andrej Karpathy on 2 February 2025. Vibe coding accelerates prototyping but produces code that typically requires professional review and hardening before production deployment.
See also: Vibe Coding to Production
W
WebSocket
A WebSocket is a persistent, bidirectional communication channel between a client (browser or app) and a server, established over a single HTTP connection upgrade and maintained until explicitly closed. Unlike HTTP, which is request-response, WebSockets allow the server to push data to the client at any time without a client request. WebSockets are used for real-time applications: live chat, collaborative document editing, live dashboards, presence indicators, and push notifications. Socket.io is the most widely used WebSocket library for Node.js.
See also: Node.js Development Company
WooCommerce
WooCommerce is an open-source eCommerce plugin for WordPress that transforms a WordPress site into a full-featured online store. WooCommerce handles product catalogue management, shopping cart, checkout, payment gateway integration, order management, and shipping. Because it runs on WordPress, WooCommerce stores have full SEO control and unlimited customisation capability. WooCommerce is free to install; revenue comes from paid extensions for subscriptions, bookings, memberships, and advanced payment gateways.
See also: WordPress & WooCommerce Customisation
Z
Zero-Click Search
A zero-click search is a search engine query where the user's question is answered directly on the search results page — through a featured snippet, AI Overview, knowledge panel, or rich result — without the user clicking through to any website. Zero-click searches represent a growing proportion of total Google searches. For content publishers, optimising for zero-click means accepting visibility (appearing as the cited source) without a corresponding click, or structuring content to appear in AI Overviews and knowledge panels that do drive brand recognition.
See also: AI SEO Agency
Need help building any of these into your project?
CV Infotech has been building web applications, AI integrations, and SEO-optimised sites since 2012. If a term in this glossary describes something you need to implement, we can help.