Glossary
Operational definitions of modern digital key terms. Explained without fluff, with references to real use cases.
Digital technologies generate new terminology every 6 months. Each year someone among iOS, Google, OpenAI changes the rules and new concepts emerge that become mandatory understanding for anyone managing a serious ecommerce or website.
This glossary collects the most relevant terms of 2025-2026, each with: operational definition (not abstract), why it matters, when it concerns you, link to the related service. Designed for business owners, marketing managers and internal teams working on web projects.
The logic is: understanding these 4 terms allows you to read a quote correctly, ask the right questions to those proposing a project, and understand where your site is leaving opportunities on the table.
Where to start
No need to read everything in order. Each of these 4 terms is important for different profiles. Identify yours and start there.
Investing in Google Ads, Meta Ads, TikTok Ads? Your tracking data is probably 30-50% incomplete, so campaigns aren't optimized.
Start with: server-side tagging + Conversion API (CAPI)
Want to be found on AI engines (ChatGPT, Perplexity, Gemini) when customers search your category? It's a new channel already worth 20-30% of traffic in some industries.
Start with: GEO (Generative Engine Optimization)
Someone proposed a headless site and you want to understand if it makes sense or it's just tech fashion. The answer depends on scope and budget.
Start with: headless commerce
Want a quick reference to explain to clients why certain setups have become standard. All 4 terms are useful in briefing phase.
Start with: GEO and server-side tagging
The terms
AI / SEO
SEO evolution for ChatGPT, Perplexity, Gemini, Claude.
Site optimization so AI generative engines cite it when answering user queries. Different from classic SEO because content's citation-friendliness matters more than ranking.
Read more on GEO →Tracking / Analytics
Tracking that actually works after iOS 14.
Analytics tracking technique sending events to the server instead of the browser. Bypasses ad blockers and cookie blocking, recovers data lost client-side. Modern standard for serious ecommerce.
Read more on server-side →Tracking Meta / Ads
Meta server-to-server channel for real ROAS.
Meta server-side API to send conversion events directly from server. Recovers data on Mac/iPhone where iOS 14 ATT blocks the JavaScript Pixel.
Read more on CAPI →Architecture
Frontend decoupled from ecommerce backend.
Ecommerce architecture where frontend (user site) is separated from backend (products, orders, cart) and communicates via API. Custom React/Vue/Next.js frontend with WooCommerce, Shopify, Magento backend.
Read more on headless →Timeline
Each of these changes generated one of the glossary terms. Understanding the "why" helps understand the "what to do".
First headless architectures
DTC brands start experimenting with decoupled frontends (React + Shopify Storefront API) to improve performance and custom UX.
→ Headless commerceiOS 14 + ATT — client-side tracking collapses
Apple introduces App Tracking Transparency. Meta Pixel, Google Pixel and JavaScript tracking lose 30-60% of events on Apple devices. The server-side era begins.
→ Server-side tagging + CAPI3rd-party cookies phase-out begins
Safari ITP, Firefox ETP and Chrome start blocking 3rd-party cookies. Client-side tracking becomes increasingly unreliable. Server-side becomes standard.
→ Server-side taggingChatGPT massive launch
ChatGPT exceeds 100 million users in 2 months. Starts replacing Google for informational queries. Companies start asking: how to be cited by LLMs?
→ GEOllms.txt + Schema.org for LLMs become standard
llms.txt standard emerges (Jeremy Howard, September 2024). Anthropic, Vercel, Stripe and Cloudflare adopt it. GEO becomes concrete practice, not just theory.
→ GEOConvergence: all terms are standard
Server-side tagging, CAPI, llms.txt, structured Schema.org are now the baseline setup for any serious ecommerce. Not having them means leaving money and visibility on the table.
→ All glossary termsComing soon
We're expanding the glossary over time. These terms will get a dedicated page in coming months.
The 3 performance metrics Google uses as ranking signals: LCP (Largest Contentful Paint), INP (Interaction to Next Paint, replacing FID since 2024), CLS (Cumulative Layout Shift). Below certain thresholds, the site gets demoted.
Technique to give an AI chatbot knowledge of specific corporate documents (manuals, FAQs, product catalog). The AI searches documents before answering, reducing hallucinations. Standard for custom chatbots on internal knowledge base.
Website that behaves like a mobile app: installable, offline-capable, push notifications, device hardware access. Low-cost alternative to native iOS/Android apps for many use cases.
Standard for structured data that lets Google and LLMs understand page content (is it an article? a product? a FAQ? an organization?). Without JSON-LD no Google rich results nor reliable LLM citation.
Data collected directly from the customer (email signup, site behavior, order history), opposed to third-party broker data. With 3rd-party cookie phase-out, first-party data has become the most precious asset for marketing and personalization.
Looking for a specific term not yet covered? Write to us and we'll add it in the next update.
In a 10-minute free call we'll honestly tell you which of these terms are relevant for your project and which aren't. Without selling you anything you don't need.
