Lesson 1 / 29
What Prompt Engineering Is
Define prompting as designing inputs and testing them like software.
Designing the input, measuring the output
A prompt is the text (and sometimes images or files) you send to a language model. Prompt engineering is the practice of designing that input so the model's output is useful, correct and consistent, then testing it on realistic examples and improving it. It is not magic words: models predict likely continuations, so a clear, complete, well-structured request makes the right continuation more likely. The skill combines clear writing, knowing what the model can and cannot do, and the engineering habit of changing one thing at a time and measuring.
Instructions in, behaviour out
A prompt is the only lever you have over a model at run time, so its structure matters.
Briefing a new colleague
Imagine handing a task to a smart new colleague who knows nothing about your company. Vague instructions give vague work; a clear brief with examples gives what you wanted.
Treat prompts as code
Keep prompts in files, review changes, and test them. A prompt that only lives in someone's chat history cannot be improved reliably.
Quick check: What is prompt engineering, best described?
- Retraining the model weights
- Finding secret magic words
- Designing and testing inputs so model output is useful and consistent
- Writing longer prompts always
Answer
Designing and testing inputs so model output is useful and consistent — It is a design-and-measure discipline, not a trick.