What An Argument Isn’t. Let’s start with our old friend the dictionary. An argument in an essay is none of the following:
 A heated debate
 A quarrel
 A dispute
 A disagreement
What An Argument Is. The novelist Thomas Hardy wrote in the ‘Preface’ to Tess of the D’Urbevilles that ‘A novel is an impression, not an argument’. This underlines that an argument has a definite structure and is organised for a definite purpose. Back at the dictionary, here are some useful ways of thinking about an argument in an essay:
 A course of reasoning aimed at demonstrating a truth or falsehood.
 A set of statements in which one follows logically as a conclusion from the others.
 The act or process of arguing, reasoning, or discussing.
 A coherent series of reasons, statements, or facts intended to support or establish a point of view.
Key Words. All these definitions underline essential features of an argument. Let’s isolate some key words from each definition. An argument is ‘a course’, ‘a set of statements which follow logically’, ‘a process’ and ‘a coherent series’. These key words tell us three important things about an argument:
 An argument is something that moves from a definite starting point to a definite conclusion.
 An argument is made up of a number of smaller parts that are clearly linked together.
 An argument is made up of a number of smaller parts organised in a developmental order i.e. one part leads naturally to the next.