In the event that I have readers unfamiliar with the school of Economics, don't shy away. All people have the ability to contribute to this school of thought. In general, all economists study the motivation people have for selecting goods and services with their limited resources. All you need to participate is some personal insight and some curiosity in others rationale for their decisions.
Microeconomics focuses on those atomic level decisions like if you pick whole milk over 2% or a red-colored package over a green-colored package.
Macroeconomics focuses on what happens when all of us make decisions simultaneously, and how policy and/or regulatory actions can be enacted to avoid large scale societal problems.