Guided pathThis is part of Understand Transformers & BERTBack to the path

What is a model? What is an algorithm?

P10.orientation.01 · Audience: guest, it-ml, language-pro

Two words appear everywhere in AI — model and algorithm — and almost every later idea rests on them. Take them one at a time, starting from things you already know well: a map, a grammar, a recipe. No maths, no code. Your glossary is one click away whenever a term is new.

🗣️ From a linguist's perspective: a model is like a grammar

A grammar is not the language itself — it is a compact description that captures how the language tends to behave, useful enough to teach, translate and correct with, while quietly leaving out countless exceptions. That is exactly what a model is: a deliberate simplification of something real, kept because it is useful, not because it is complete. When you reach for a grammar rule instead of every sentence you have ever heard, you are already using a model.

The territory (everything)simplifyA street map (a useful model)keeps streets · drops the rest
A model is a useful simplification: like a street map, it keeps what the task needs and drops the rest.
Step 1 / 3A model is a useful simplification

A model is a simplified stand-in for something in the real world — small enough to reason with, close enough to be useful. The classic example is a map. A city map leaves out almost everything: the weather, the traffic, the colour of the doors. It keeps just enough — streets and their connections — to answer one kind of question well: how do I get from here to there?

The famous saying is “the map is not the territory”. A model is never the real thing; it is a chosen simplification. A good model keeps what matters for its job and drops the rest on purpose. So the useful question is never “is this model true?” but “is it useful for this task, and where does it break?”

Worked example — three models of the same city

A street map, a metro map and a tourist map all model one city. The metro map even distorts distances so the lines stay readable — and that distortion makes it better at its one job. Same reality, different simplifications, each right for a different question. A language model is a model in exactly this sense: a simplified stand-in for how language behaves, built to answer “what text is likely to come next?”

📚 Go Further

Plain-language explainers on models and algorithms — no maths required.

  • Model — a simplified, useful stand-in for something real; see your glossary.
  • Algorithm — a fixed, repeatable set of steps; see your glossary.
  • “The map is not the territory” — Alfred Korzybski's phrase, the one-line summary of what a model is and is not.
Ask the mentor about this module

Ask a question about this content. The mentor explains and grounds its answer in what you are studying; asking is recorded as a learning signal, not a grade.

Ctrl/Cmd + Enter to send