Beginner · Lesson 1 of 6 · 10 min
What AI actually is
Sort out AI, machine learning, generative AI and large language models, and learn what a model can and cannot do before you build anything on it.
Four terms, one inside the other
Artificial intelligence is the broad field: software that handles tasks we normally associate with human judgment, such as recognising speech, sorting messages or writing text.
Machine learning is one way to build AI. Instead of writing every rule by hand, you show the system many examples and it learns the patterns. A spam filter or a lead-scoring model is machine learning. It outputs a label or a number, not new content.
Generative AI is machine learning that produces new content: text, images, audio or code. A large language model (LLM) is the generative kind you will use most. It is trained on a very large amount of text and produces text in response to text.
This matters when you evaluate tools. When a vendor says a feature is AI-powered, ask which kind. A scoring model and an LLM fail in different ways and need different checks.
What an LLM is doing when it answers
An LLM starts life through pretraining: it reads a huge body of text and learns to predict the next word given everything before it. Anthropic's glossary notes that a model at this stage is not good at answering questions or following instructions. Further training turns it into an assistant that follows instructions.
When you send a prompt, the model generates its reply one small piece at a time, each piece chosen because it fits what came before. It is not looking anything up unless the app around it gives it a search or retrieval tool. It is producing the most fitting continuation based on patterns it learned.
Many current models are also multimodal, meaning they can take images or documents as input as well as text. The core behaviour is the same: input in, generated output out.
What models are good at
LLMs are strong at work that involves messy language: summarising a long email thread, drafting a reply, pulling a name and phone number out of a free-text form, classifying a support ticket, rewriting copy for a different audience, or translating.
A realistic business example: a lead fills in a contact form with a rambling paragraph. A model can turn that paragraph into a one-line summary, a service category and an urgency flag that your CRM can store. A rule-based filter would struggle because no two leads phrase things the same way.
What a model cannot do on its own
A model has no knowledge of events after its training data ends unless you supply it. It cannot take actions such as sending an email or updating a contact unless it is connected to tools. It can be confidently wrong, and the same prompt can produce different wording each time.
It also does not remember you between separate conversations unless the app stores memory and feeds it back in. And it is the wrong tool for exact, repeatable work like adding up invoice totals or checking whether a date has passed. A formula or a normal automation step does that reliably and for free.
A useful rule from day one: deterministic tasks get deterministic automation. Use a model where the input is unstructured language and some judgment is needed, and check its output where mistakes are costly.
Key points
- ◆AI contains machine learning, which contains generative AI, which includes LLMs.
- ◆An LLM generates likely text from learned patterns; it does not look things up unless given a tool.
- ◆Models are strong at unstructured language tasks: summarising, drafting, classifying and extracting.
- ◆Models lack live knowledge, cannot act without tools and can be confidently wrong.
- ◆Use plain rules and formulas for deterministic work; reserve models for judgment on messy input.
Terms in this lesson
Try it · exercise
Sort five real tasks from your own week into work a model should do, work a rule or formula should do, and work a person must keep, then test one model task.
- List five recurring tasks from your work, such as replying to enquiries, updating a spreadsheet or writing a weekly summary.
- Label each one: model (messy language, some judgment), rule (exact and repeatable), or person (high stakes or relationship-critical).
- Pick one model task and try it in a free chat app with a real but non-sensitive example.
- Read the output line by line and mark each statement as correct, wrong or unverifiable.
You're done when: You have a list of five tasks with a label and a one-line reason for each, plus one chat output where every statement is marked correct, wrong or unverifiable.
