"welcome" so it appears in the "Introduction" section of the installer (the
"Readme" page doesn't appear anymore). Previously the Introduction page was
just a useless extra page that said "You will be guided through the steps
necessary to install this software."
metapackage (.mpkg) installer. The installer lets you pick if you want to
install Nmap or Zenmap or both. It puts Nmap in /usr/local and the previously
developed Zenmap.app in /Applications.