A good introduction pulls the reader into the text, helping the reader know what to expect and how to approach the text. In the introduction to academic papers, the writer might begin with a thesis and then provide supporting examples for the thesis. Or the paper might set a context that leads up to the thesis. Whatever your strategy, you want to engage and orient the reader.
An introduction for a brief essay might be a single paragraph. For longer papers, an introduction might be two or three paragraphs.
Strategies for writing an introduction
Providing a hook in your introduction
Exercise: Introductions
Related topics:
Placing the thesis statement within the introduction
Drafting the body
Drafting a conclusion