Glossary
Data and AI terms, in plain words.
The technical, business and engineering terms used on this site, explained simply.
A
- A2A (Agent2Agent)
- The open protocol that lets agents talk to each other and share work. MCP links an agent to a tool; A2A links two agents.
- Accounts payable
- The function that receives, checks and pays supplier invoices.
- AG-UI
- The open protocol connecting an agent to the application the user sees: live answers, visible actions, approval requests.
- Agent
- A program that uses an AI model to carry out a task: it reads information, calls tools and suggests or performs actions.
- Agent card
- A small file published by an A2A agent describing what it can do, where to reach it and how to authenticate.
- Agentic AI
- AI that does more than answer: it chains steps together and acts in tools to reach a goal.
- API
- The interface that lets two pieces of software exchange data automatically.
- API management
- The platform that publishes, secures, documents and monitors a company’s APIs (MuleSoft, Kong, Azure API Management…).
- Audit log
- The record of who did what, when and with which data. It lets you check and explain every action.
- Azure AI Search
- Microsoft Azure’s search engine, which indexes documents so they can be found by keyword or by meaning.
- Azure Functions
- A Microsoft Azure service that runs code on demand, without managing servers.
B
- Backup generator
- An engine, often diesel, that produces emergency electricity when the grid fails. Its thermal power exceeds its electrical output.
- Behind the meter
- Electricity generation installed on the consumer’s own site, off the public grid: turbines, engines, fuel cells.
C
- CDU
- Coolant Distribution Unit: the unit that separates and exchanges heat between the chips’ liquid loop and the building’s water loop.
- Centre of excellence
- A small cross-functional team that sets standards, approves models, owns the responsible AI framework and equips other teams.
- CI/CD
- Continuous integration and delivery: the automated chain that tests, approves and ships code.
- Classified installation
- An industrial facility that presents risks or nuisances and is subject to stricter environmental rules (ICPE in France).
- Client Credentials
- MCP extension where the agent connects with its own technical credentials: this is the machine-to-machine mode.
- Combined cycle
- A gas plant that recovers heat from its turbines to produce more electricity. It is the most efficient gas technology.
- Conditional access
- Rules that allow or block access depending on context: device, location, risk level.
- Connector
- The link between an agent and a company application (email, tickets, CRM, ERP) that lets it read or write there.
- Container
- An isolated package holding an application and everything it needs to run, identically on any server.
- Corporate directory
- The system listing employees, their groups and their rights (Microsoft Entra ID, Okta…).
- CRM
- Customer relationship management software: contacts, opportunities, interaction history (Salesforce, for example).
- CSRF
- An attack that makes a browser send a request without the user knowing. A CSRF token in each form prevents it.
D
- Data center
- A building that hosts servers, storage and networking, powered and cooled continuously, day and night.
- Data warehouse
- A database organised for analysis: cleaned, linked data ready for dashboards.
- Declarative agent
- An agent described in a configuration file (role, instructions, model, tools, rights) instead of being coded. It can be reviewed, approved and versioned.
- Deduplication
- Spotting and removing duplicates, for example two articles about the same project.
- Deep Agents
- An open-source LangChain library: a main agent that plans, takes notes in a file system and delegates to subagents.
- Delegated rights
- The user hands the agent only part of their rights: a precise scope, a limited time, revocable at any moment.
- Deterministic
- Always producing the same result for the same input. A classic flow is deterministic; an agent deciding on its own is not.
- Dew point
- The temperature at which moisture in the air condenses. The higher it is, the more humid the air and the harder it is to use for cooling.
- Dry cooler
- A heat exchanger that cools a liquid with outside air, without evaporating water. It uses a bit more electricity than an evaporative tower.
E
- Embeddings
- A numeric representation of text or images that lets you find content close in meaning.
- ERP
- Enterprise resource planning software: finance, purchasing, inventory, production.
- Evaluation
- Testing an agent on a set of known cases to measure the quality of its answers before updating it.
F
- False positive
- A result wrongly flagged as relevant: here, an article raised as an opportunity when it is not one.
- Federated model
- An organisation where business teams build their own use cases on a shared foundation run by a platform team.
- FinOps
- The practice of managing and optimising cloud spending, bringing finance, procurement and engineering together.
- Framework
- A development toolkit that provides an application’s structure; for agents: LangGraph, Strands, CrewAI…
- Free cooling
- Cooling a data center with outside air rather than a refrigeration machine. Only possible when it is cool and dry enough.
- Front end
- The interface where employees use AI: chat window, list of assistants, documents to attach.
G
- Gateway
- A single checkpoint placed in front of services, controlling everything that goes in and out: identity, rights, quotas, logging.
- GPU
- Graphics processing unit: the massively parallel chip used to train and run AI models. It is what draws and heats the most.
- Guardrails
- Automatic checks that block risky use: sensitive data leaks, forbidden content, out-of-scope actions.
H
- Hook
- A point where you can run your own code at a precise moment: before a tool call, after an answer, when an agent stops.
- Human approval
- A person reviews and approves before the agent’s action is carried out (also called human in the loop).
- Hyperscale
- The very large data centers of cloud giants (AWS, Microsoft, Google, Meta), sized in tens or hundreds of megawatts.
I
- Idempotency key
- An identifier attached to a write request: if the same request is sent twice, it has a single effect, with no duplicate.
- Identity propagation
- The agent acts on behalf of the person using it, with their rights: it only sees what they are allowed to see.
- Identity provider
- The service that authenticates users and issues their access tokens (Microsoft Entra ID, Okta, Keycloak…).
- Impact assessment
- The file that assesses a project’s effects on the environment (water, air, noise, biodiversity), mandatory above certain thresholds.
- Interconnection queue
- The list of projects (power plants, storage, large consumers) waiting to be connected to the transmission grid.
- Interface contract
- The stable commitment between the platform and applications: what is offered, how to call it, with which guarantees, without exposing internals.
- Isolated runtime
- The environment an agent runs in, separated from others and limited to its scope, to contain errors and misuse.
- ITSM
- IT service management: tickets, incidents, requests and changes (ServiceNow, for example).
J
- Jevons paradox
- When a resource becomes more efficient to use, people use more of it, and total consumption can rise.
- JSON
- A simple text format for exchanging structured data between programs.
K
- Knowledge base
- The reference documents an agent can look up to answer: procedures, documentation, history.
- Kubernetes
- The leading open-source platform for running and managing containers at scale.
L
- Lakehouse
- A storage space that keeps large volumes of raw data while letting you query it like a database.
- Liquid cooling
- Removing chip heat with a liquid rather than air: cold plates on the chips (direct-to-chip) or servers immersed in a fluid (immersion).
- LLM
- Large Language Model: a model such as those from Mistral, OpenAI or Anthropic, able to understand and produce text.
- LLM gateway
- The single checkpoint for every call to a model: model choice, quotas, cost, filtering and logging.
- LLMOps
- The practices and tools for running language models in production: deployment, versions, quality, cost and incident tracking.
- llms.txt
- A file at the root of a website that gives language models a one-page map of it: what it contains and where to read it.
- Load balancer
- The component that spreads requests across several servers to handle load and avoid outages.
M
- Machine to machine
- Two applications talk directly, with no user involved, using a technical account. Reserved for data everyone may see.
- Manifest
- The file describing an application or an agent: its name, capabilities and permissions.
- Markdown
- A text format readable as is, with a light syntax for headings, lists and links. Ideal for humans and models alike.
- Market monitoring
- Regularly following the news of a market to spot projects, competitors or trends.
- MCP (Model Context Protocol)
- The open standard that lets an agent use tools and data: read tickets, search documents, query a CRM.
- MCP gateway
- The mandatory path between agents and MCP servers: authentication, per-tool rights, rate limits, filtering and logging.
- MCP server
- The small service that exposes a tool (an application, a document base) to agents through the MCP protocol.
- Megawatt (MW)
- A unit of power: what must be supplied at every instant. 1 MW = 1,000 kW. Not to be confused with the megawatt-hour, which measures an amount of energy used over time.
- Microsoft Fabric
- Microsoft’s data platform bringing together storage, transformation, analysis and Power BI dashboards.
- MicroVM
- A very lightweight virtual machine that starts in a fraction of a second and isolates a program from the rest of the server (Firecracker, for example).
- Middleware
- A component that slots into an agent’s loop (before or after the model, around a tool) to add a control without changing the agent itself.
N
- No-code
- Building a tool through a graphical interface, without writing a program.
O
- OAuth 2.1
- The standard for giving an application limited access to a service without handing over your password.
- Observability
- Seeing what happens inside agents: every run, its sources, tool calls, errors and costs.
- Open source
- Software whose code is public and reusable under a licence. It can be audited, self-hosted and modified.
- Orchestration
- Coordinating several agents and tools to run an end-to-end process: who does what, in which order, with which checks.
P
- PJM
- The largest grid operator and electricity market in the United States (Virginia and twelve other states). Its capacity auctions pay for power available at peak times.
- Power BI
- Microsoft’s dashboard and data visualisation tool.
- Preprint
- A scientific paper published before peer review. Its results should be read with caution.
- Prompt
- The written instructions given to the AI model to steer its answer.
- Prompt injection
- Instructions hidden in content (a document, email, ticket) that the agent reads and may follow as if they came from the user.
- PUE
- Power Usage Effectiveness: a data center’s total energy divided by the energy reaching the servers. 1.0 would be perfect; 1.5 means 50% extra energy for cooling and losses.
- Purchase order
- The document formalising a purchase from a supplier: items, quantities, prices. The invoice must match it.
R
- Rack
- The standard cabinet that holds servers: 60 cm wide, about two metres tall. Its power is measured in kilowatts.
- RAG
- Retrieval-Augmented Generation: the model first retrieves the right passages from your documents, then writes its answer from them, citing sources.
- Rebilling
- Charging each team the real cost of its AI usage, to manage the budget.
- Registry
- The central, versioned catalogue of everything agents use: agents, skills, prompts, tools and MCP servers.
- REST
- The most common style of web API: data is exchanged through addresses and simple verbs (read, create, update, delete).
- Reverse proxy
- A server placed in front of others that receives every request and forwards it while applying rules.
S
- SaaS
- Software as a Service: software used online, hosted and maintained by the vendor, paid by subscription.
- Sandbox
- An isolated environment where code runs without risk to the rest of the system: what happens inside cannot get out.
- Scoring
- Giving an item a score against defined criteria, to rank it or decide whether it deserves attention.
- Self-hosted
- The software runs on the company’s own infrastructure (its servers or cloud), not at the vendor’s. Data stays with you.
- Semantic similarity
- A measure of how close two texts are in meaning, even when they use different words.
- Service account
- A technical account, owned by no person, used by one application to connect to another.
- Shell
- A system’s command-line interface: you type commands to read files, run programs and so on.
- Skill
- A reusable know-how for an agent: a folder of instructions, templates and sometimes scripts, loaded only when needed.
- Sovereignty
- Keeping control of your data and tools: hosting in Europe, applicable law, no dependency on a foreign provider.
- SSO
- Single Sign-On: one login, with the company account, to access every tool.
- Stateless
- A service that keeps no memory between requests: each call stands alone, so it can easily be spread across several servers.
- Subagent
- An agent called by a main agent for a precise task, with its own context; it returns a result, the main agent decides.
- System prompt
- The standing instructions given to an agent: its role, its rules, how it works.
T
- Talk to my data
- Asking questions in everyday language about your data (sales, costs, stock) and getting sourced, quantified answers.
- Token
- Two meanings. For a model: a piece of a word, the unit that measures processed text and therefore cost. In security: a temporary key proving an access right.
- Token exchange
- The gateway swaps the user’s token for a new one, issued for a specific service with reduced rights (OAuth standard, RFC 8693, also called “on-behalf-of”).
U
- Urban heat island
- A built-up area warmer than the surrounding countryside, because concrete and human activity store and release heat.
- Urgent-procedure judge
- The judge who rules urgently, for example to suspend a decision pending a ruling on the merits.
V
- Versioning
- Keeping every change to a file with its author and date, so you can compare, review and roll back.
W
- Waste heat
- Heat produced by an activity and released without being used. Data-center heat can warm homes.
- Watt-hour (Wh, kWh, TWh)
- A unit of energy: a power sustained over time. 1 kWh = 1,000 W for one hour; 1 TWh = a billion kWh.
- Workflow
- A sequence of steps defined in advance. Some steps can be handed to an AI model, but the order stays fixed.
- WUE
- Water Usage Effectiveness: litres of water consumed per IT kilowatt-hour.
Y
- YAML
- A human-readable text file format, widely used to write configuration.
Z
- Zero Trust
- A security model where nothing is trusted by default: every access is checked, even inside the network.