Gee, This is one of those dificult ones - kinda like the network monitoring one, because I actually mix and match and use more than one in a single place at any given time.
Basically, tar and rsync MUST be listed (and are right up there on top in the poll too LOL), while I also use others in the list regularly too, such as Clonezilla, Bacula (for enterprise disaster recovery to augment tar and rsync implementations that are ALWAYS incorporated), and luckybackup is really good too for many applications.
Years ago Bru was in the list LOL.
Does anyone still use Amanda?
Anyway, if I had to pick only three, they would be *tar*, *rsync*, and *Bacula*.....
But we can only pick one in the list above.... tar or Bacula.... tar or Bacula.... Okay then. tar is the original, and I think we all pretty much rely on it regardless, along w/rsync, so the one I picked from the list above was......
I hope that helps!