Aren't Haplotypes used in reference to mtDNA in addition to Y-DNA tests?
Quick and very basic
DNA test reference reminder (for original poster):
Y-DNA tests male lineages, only males of a line can test
mtDNA tests maternal lineages, can test M and F
Autosomal DNA (also known as AncestryDNA) tests SNPs
to find similarities, does not provide Haplogroups.
Each test has different values and different things that it reveals and helps genealogists in different ways.