A good prompt tells the model four things: what to do, who it is for, what limits apply and what the answer should look like. Most weak prompts miss one of these. They ask a vague question, leave out the audience, give no length or scope, or never say whether the answer should be a list, a table or JSON. Delimiters such as tags or headings help the model tell your instructions apart from the material it should work on.
These beginner guides explain what prompt engineering is, show how to write a clear prompt with a task, role, constraints and output format, and how to give the model the context it needs. Each comes with before and after examples you can try in any chat model.
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