how do I check the \listfiles command

Question

How do I check that the \listfiles command works? When I give it in front of \begin{document} OR I delete it, no difference appears to happen.

Answer 1

\listfiles puts its output into the log file (if your tex file is named something.tex, the log file will typically be named something.log). It also puts the output into the terminal (if you are compiling the document from a terminal).