Start with your research question and break it into 2 or 3 concepts. These become your keywords or phrases which form the basis for your search. Keywords are joined by the connectors AND and OR to narrow or broaden your search.
Boolean Logic is a fancy term for a simple concept. Boolean operators are the connecting terms AND and OR used when constructing searches in the databases. It's called Boolean because it was named after a famous mathematician, George Boole, who developed it.