Most writing is based on some form of argument, even writing that is based on original research findings. The most common understanding of argument in student papers is the thesis statement (controlling idea and position on a topic) that is supported by evidence from sources. In research writing, argument is present when the writer convinces the reader of the importance of a problem and necessity for research. Argument is also present when convincing the reader to believe your interpretation of data.
The structure of academic arguments varies from simple forms where a thesis statement may have helped you organize paragraphs when you were learning English and writing a 4 or 5-paragraph essay to more complex forms of proposals supported by evidence and explanation. In everyday life, we engage in "argument" when we try to convince someone else of our point of view. Our argument is a claim (an assertion) that is followed by reasons, explanations, and evidence to support it.