traceroute
NetworkPackage: traceroute
Prints the successive routers to a destination, by sending packets whose TTL rises by one each time: the router that brings it to zero names itself by returning a Time Exceeded. A * means only that this router did not answer, not that traffic stops there. Not installed by default on Ubuntu 24.04; ping -t does the same thing one hop at a time, with nothing installed.
What its options do in the lessons
From the same glossary the lessons render under their commands, so the two cannot disagree.
traceroute -n- Prints addresses without looking up a name for each one. Faster, and essential when the failure being diagnosed is name resolution itself.