One example is better than thousand of words. I'm working on lvm2 community now. Say, I want to download the history mail archives from lvm-devel maillist. Straightly, the following command will do the task for me:
wget -m -r -nH -np --cut-dirs=2 --reject="index.html" -Atxt.gz --no-directories --level=1 robots=off https://www.redhat.com/archives/lvm-devel/
man wget will explain the parameters in the command.