I admit I was confused when I first saw genealogists list haplogroups for the different Y and mitochondrial lines within their pedigree chart. But fast forward a few years and now I have tried a few different lines within my own family. So the completist in me is eager to try to find out what haplogroups my other recent ancestors had.
Of course, you don't need to have organized dedicated Y or mitochondrial tests to get this information. 23andme and LivingDNA provide high-level haplogroups.
And if your matches are good enough and you've tested on 23andme, you may be able to collect some mt or Y haplogroups from the match details. Gedmatch also has self-report fields for this information.
Tree showing mitochondrial haplogroups
My son's tree with mitochondrial haplogroups
When you save, these haplogroups will propagate within your tree:
Adding or editing a Haplogroup Y for a male will apply it to his male line ancestors and male line descendants
Adding or editing an mt haplogroup for anyone will apply it to their female line ancestors. For a woman, this will also apply to her sons / daughters.
If you have pedigree collapse, this will happen for all instances of this person in your tree
When you view a person's details overlay, all haplogroups will be displayed. You will also see a link to the appropriate FamilyTreeDNA haplotree tree node.