Definition of Introduction and its Functions.
When you meet new people, you start with introducing yourself. You tell who you are and what you do, you try get you new acquaintance interested in further conversation. Draw an analogy with an essay. This is exactly what an introduction means. There are a lot of synonyms used to depict the essence of introduction; for example prologue, preface, foreword, overture and the others, but all of them possess the same meaning: a short preview on what you are going to write, or tell, or play. Speaking in terms of writing, an introduction is a segment of a body-structure of an essay, where the author introduces the topic of an essay in brief and reveals reasons for choosing it for an assignment topic.
Let's draw another parallel to the structure of the play. An experienced script-writer is to describe the sequence of time, place and way of action without revealing the extracts of action itself. The functions of introduction are exactly the same. A foreword is created to present the thesis statement of an essay, to make a reader interested in your opinion, to show perfect knowledge of a subject and related thoughts. A task of any author is to stay focused on the tasks mentioned above and compose an introduction accordingly.