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Glossary

The terms, in plain language

Short answers to the words that come up when people talk about data, AI, cloud and software. Each one links to where it is used.

In short

This glossary explains the technical terms used across this site, in two sentences each. Every term links to the solution or capability where it comes up, so you can see it in context. You do not need to know any of them to start a conversation.

Last updated

A

Agentic workflow

An agentic workflow is a business process in which an AI agent carries out some of the steps, deciding what to do next based on what it finds. It fits work that follows a pattern but needs judgment along the way, and it needs clear limits on what the agent may access and do.

AI agent

An AI agent is a software program that uses a language model to decide which steps to take toward a goal, and that can call tools such as search, databases or other systems to carry them out. It matters because it can handle a multi-step task instead of only answering a question, which makes its permissions and oversight important design choices.

AI evaluation

AI evaluation is the practice of testing an AI system against a set of realistic questions or tasks with known good answers, and scoring the results. It turns a hunch that the system works into evidence, so a team can see whether a change to the prompt, data or model made it better or worse.

AI gateway (Model gateway)

An AI gateway is a single service that sits between an application and the language models it calls, handling routing, access control, logging and limits in one place. It keeps those concerns out of each application and makes it easier to switch or add models later.

Application programming interface (API)

An application programming interface, or API, is a defined way for one piece of software to ask another for data or an action, without needing to know how the other works inside. APIs let separate systems, such as a website and a billing tool, work together through a stable, documented contract.

Architecture decision record (ADR)

An architecture decision record is a short written note that captures one important technical decision, the options considered and the reasons for the choice. It preserves the thinking behind a system, so people who join later can understand why it was built that way.

B

Build versus buy

Build versus buy is the decision between writing custom software and adopting an existing product or service for a need. The right answer depends on how central the need is to the business, what each route costs over time and how much control is required.

C

Change data capture (CDC)

Change data capture is a technique that detects inserts, updates and deletes in a database as they happen and passes them on to other systems. It lets a copy of the data stay current without reloading everything, which supports reporting and integrations that depend on fresh data.

Chunking

Chunking is the step of splitting long documents into smaller passages before they are indexed for search by an AI system. Good chunks are small enough to be relevant and large enough to keep their meaning, which strongly affects whether the right passage is found.

Container orchestration

Container orchestration is the automated management of containers, which are lightweight packages that bundle an application with what it needs to run. It handles starting, scaling, updating and replacing them across many machines, to help applications stay available as demand and releases change.

Continuous integration and delivery (CI/CD)

Continuous integration and delivery, known as CI/CD, is a practice in which every code change is automatically built and tested, and approved changes are released through a repeatable pipeline. It reduces manual steps and can make releases routine.

D

Data contract

A data contract is an agreement between the team that produces data and the teams that use it, describing the fields, formats, meaning and expectations for that data. It makes changes visible before they break the reports or integrations that depend on it.

Data governance

Data governance is the set of rules, roles and practices that decide who owns data, who can use it and how it is kept accurate and protected. It matters because people can only trust and safely share data when responsibility and access are clearly defined.

Data lake

A data lake is a central store that holds large amounts of raw data in its original form, structured or not, at low cost. It gives analysts and data scientists one place to draw from, though it needs good organization so it does not become a pile of unusable files.

Data lineage

Data lineage is a record of where data came from and every step that changed it on the way to a report or model. It lets people trace a surprising number back to its source, and it helps check what a change would affect before it is made.

Data mart

A data mart is a focused subset of an organization's data prepared for one team or subject, such as finance or sales. Because it is organized around the questions that team asks, reports built on it can be quicker to create and easier to understand.

Data mesh

Data mesh is an approach in which individual business domains own and publish their data as products, supported by shared platform tools and common standards. It suits larger organizations where one central data team has become a bottleneck.

Data pipeline

A data pipeline is an automated series of steps that moves data from its sources, cleans and reshapes it, and delivers it where it is needed. It replaces manual exports and copying, so reports and applications receive consistent data on a schedule or in real time.

Data quality

Data quality describes how accurate, complete, consistent and timely data is for the purpose it serves. Checking it as data flows through a system catches problems early, before they reach reports and decisions.

Data warehouse

A data warehouse is a database designed for analysis, holding cleaned and organized data from many sources in a consistent structure. It gives a business a single reliable place to answer questions across the whole organization.

DevSecOps

DevSecOps is a way of working that builds security checks into every stage of software development and delivery, rather than adding them at the end. It helps teams find and fix weaknesses earlier, when they are easier to correct.

E

Embedding

An embedding is a list of numbers that represents the meaning of a piece of text, an image or other data, so that similar items end up with similar numbers. Embeddings let software find content by meaning rather than by exact words, which is the basis of semantic search.

ETL and ELT

ETL and ELT are two patterns for moving data into an analytics system, either extract, transform and load or extract, load and transform. The difference is whether data is reshaped before it is stored or after it arrives, which affects flexibility, speed and cost.

Event streaming

Event streaming is the continuous capture and delivery of events, such as clicks, payments or sensor readings, as they occur. It lets systems react within moments instead of waiting for a nightly batch of data.

Event-driven architecture

Event-driven architecture is a way of designing software in which components announce that something happened, such as an order being placed, and other components react to it. It keeps systems loosely connected, so parts can change or scale without being rewired to each other.

F

Fine-tuning

Fine-tuning is the process of training an existing AI model further on a smaller, specialized set of examples so it behaves in a particular way or style. It can help when prompting and retrieval are not enough, but it adds cost and upkeep, so it should be used only where justified.

FinOps

FinOps is a practice that brings engineering, finance and business teams together to understand and manage the cost of cloud usage. It makes spending visible and accountable, so cost decisions are made alongside decisions about performance and speed.

Foundation model

A foundation model is a large AI model trained on broad data that can be adapted to many different tasks, such as writing, summarizing or answering questions. A business AI feature can start from one of these models instead of training a new model from scratch.

G

GitOps

GitOps is a way of managing infrastructure and application deployments in which the desired state is stored in a Git repository and applied automatically. Changes can then be reviewed, recorded and reversed, like any other change to code.

Groundedness

Groundedness is how well an AI system's answer is supported by the source material it was given, rather than by guesses. Measuring it helps a team spot made-up statements and decide whether an assistant can be trusted for a given task.

H

Human in the loop

Human in the loop is a design in which a person reviews, approves or corrects an automated system's work at defined points. It keeps accountability with people for decisions that carry risk, while still saving effort on routine steps.

Hybrid search combines keyword search, which matches exact words, with vector search, which matches meaning, and merges the results. It can find relevant content that either method alone would miss, such as when a query includes both a product code and a general idea.

I

Infrastructure as code (IaC)

Infrastructure as code is the practice of defining servers, networks and other cloud resources in version-controlled files that tools apply automatically. It makes environments repeatable and reviewable, so they can be rebuilt or copied without manual setup.

Intelligent document processing (IDP)

Intelligent document processing is the use of software, often including AI, to read documents such as invoices or forms and pull their key information into structured data. It reduces manual re-keying and can route unclear cases to a person to check.

K

Key performance indicator (KPI)

A key performance indicator, or KPI, is a measure chosen to show how well a business is doing against a specific goal. A small set of clearly defined KPIs gives teams a shared view of progress and keeps dashboards focused on what matters.

L

Lakehouse

A lakehouse is a data platform that combines the low-cost, flexible storage of a data lake with the organized, reliable querying of a data warehouse. It lets analytics and machine learning work from one copy of the data instead of separate systems.

Landing zone

A landing zone is a pre-configured, secure foundation in a cloud account, covering things like account structure, networking, access rules and logging. It gives new workloads a consistent starting point, so each team does not have to design the basics again.

Large language model (LLM)

A large language model, or LLM, is an AI model trained on very large amounts of text that can understand and generate human language. It powers features such as drafting, summarizing and question answering, and it can produce fluent answers that are wrong, so its output needs checking.

Least privilege

Least privilege is the security principle that a person, program or AI agent should have only the access it needs to do its job, and no more. It limits the damage if an account is misused or taken over.

LLMOps

LLMOps is the set of practices for deploying, monitoring and improving applications built on large language models. It covers concerns such as prompt versions, evaluation, cost and safety, so these applications stay reliable after launch.

M

Minimum viable product (MVP)

A minimum viable product, or MVP, is the simplest version of a product that real users can use and learn from. It tests the core idea early, so a team invests further only in what proves useful.

MLOps

MLOps is the set of practices for taking machine learning models from experiments to dependable production systems and keeping them working. It covers deployment, monitoring and retraining, so a model keeps delivering value after its first release.

Model drift

Model drift is the gradual or sudden loss of a machine learning model's accuracy as real-world data or behavior changes from what the model was trained on. Monitoring for it tells a team when a model needs to be retrained or replaced.

Model routing

Model routing is the practice of sending each request to the most suitable AI model, based on factors such as the task, the quality needed, speed and cost. It lets an application use a capable model only when needed and a lighter one for simpler requests.

O

Observability

Observability is the ability to understand what is happening inside a system by examining the logs, metrics and traces it produces. It helps teams find the cause of a problem quickly and can help spot trouble before users notice it.

P

Prompt injection

Prompt injection is an attack in which hidden or malicious instructions in text, a web page or a document trick an AI system into ignoring its intended rules. It matters most when the system can take actions or reach private data, so access should be limited and inputs treated as untrusted.

Proof of concept (PoC)

A proof of concept, or PoC, is a small, time-boxed build that tests whether an idea is technically feasible and worth pursuing. It reduces risk by answering the key question before a larger commitment is made.

R

Recovery time and recovery point objectives (RTO and RPO)

Recovery time objective is how quickly a service must be restored after an outage, and recovery point objective is how much recent data a business can afford to lose. Together they set the targets that backup and disaster recovery plans are designed to meet.

Reranking

Reranking is a second pass in search that takes the top results from a first search and reorders them by how well they match the question. It helps put the most relevant passages first, which shapes the quality of an AI assistant's answer.

Retrieval-augmented generation (RAG)

Retrieval-augmented generation is a way of answering questions with a language model by first searching a trusted set of documents and giving the model the relevant passages as context. It keeps answers tied to your own information and makes it possible to show the sources behind them.

Rightsizing

Rightsizing is the practice of matching cloud resources, such as server size or storage, to what a workload actually needs. It reduces waste from oversized resources, provided performance needs are measured first.

S

Secrets management

Secrets management is the secure storage and handling of sensitive values such as passwords, API keys and tokens that software needs to run. It keeps them out of code and shared files, controls who can read them and makes them easy to replace.

Semantic layer

A semantic layer is a shared set of business definitions, such as what counts as revenue or an active customer, placed between raw data and reporting tools. It makes every report calculate the same measure the same way.

Service-level indicators and objectives (SLI and SLO)

A service-level indicator is a measurement of how a service is performing, such as the share of requests that succeed, and a service-level objective is the target set for it. Together they turn reliability into something a team can track and discuss in plain numbers.

Structured output

Structured output is a response from an AI model in a fixed, machine-readable format, such as the fields of a form, instead of free-flowing text. It lets other software use the result directly and makes the output easier to check automatically.

T

Technical debt

Technical debt is the accumulated cost of shortcuts and outdated choices in software that make future changes slower and riskier. Like financial debt, it can be a reasonable trade-off at first, but it needs to be managed or it keeps growing.

Total cost of ownership (TCO)

Total cost of ownership is the full cost of a technology over its life, including build or purchase, running, support and eventual replacement, not just the price at the start. Comparing options on this basis helps avoid choosing something that looks cheap today but costs more later.

V

Vector search finds items by comparing embeddings, which are numeric representations of meaning, rather than matching exact words. It lets a search for one phrase return content that says the same thing in different words.

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