To work out the purpose of a text, you can find clues in the language and layout. For example:

• texts that give information sometimes use headings to tell you what is in each section
• texts that advise or instruct often use bullets or numbering; the language of instructions is usually very direct, rather like a set of demands (e.g. open up the box, check you have all the parts, use a screwdriver).
• persuasive texts might use positive descriptions and special offers to persuade you.

But don't rely on these clues alone! Think about why the writer really wants you to read the text.