A Plain-English Glossary of AI Terms

Jargon can make AI feel harder than it is. Here are common terms in everyday language.
The Basics
- AI (artificial intelligence): software that performs tasks that normally need human intelligence.
- Machine learning: systems that learn patterns from data instead of following only fixed rules.
- Deep learning: machine learning using many-layered neural networks.
- Generative AI: AI that creates new text, images, audio, video or code.
- Model: the trained system that produces outputs.
- Algorithm: a set of steps for solving a problem.
Language Models
- LLM (large language model): a model trained on lots of text to predict and generate language.
- Token: a chunk of text the model processes.
- Context window: how much text the model can consider at once.
- Prompt: the instructions or question you give.
- Hallucination: a confident but false or invented output.
- Temperature: a setting controlling how varied or predictable outputs are.
Building and Improving
- Training: teaching a model from data.
- Fine-tuning: further training for a specific task or style.
- RAG (retrieval-augmented generation): looking up documents to ground answers.
- Embedding: a numerical representation capturing meaning.
- Inference: running a trained model to get an answer.
- Parameters: the adjustable values learned in training.
- Benchmark: a standard test of model performance.
Agents and Tools
- Agent: AI that plans and takes actions using tools.
- Tool use / function calling: a model requesting actions like search or calculations.
- API: a way for software to connect to a service.
- Prompt injection: hidden instructions that try to hijack an AI.
Risks and Governance
- Bias: systematic unfairness in outputs.
- Deepfake: realistic fake image, audio or video.
- Guardrails: safeguards that limit harmful behaviour.
- Alignment: making AI behave in line with human intentions and values.
- Explainability: how well we can understand why a model gave an answer.
- Provenance: records of where content came from.
Hardware
- GPU: a processor suited to parallel calculations used in AI.
- NPU: a chip in devices for AI tasks.
- On-device AI: models running locally rather than in the cloud.
Takeaway
You don't need to memorise everything. Knowing these terms makes it easier to ask good questions and cut through hype.
