Phylogeny is a statistical approach for reconstructing evolutionary relationships using trees

Phylogeny shares a close relationship with phylogenetics. A molecular phylogeny is the same thing as a phylogenetic tree.

A phylogeny doesn't need to be built using genetic data, whilst phylogenetics exclusively uses genetic data thus phylogenetics is a subset of phylogeny. A phylogeny could be used for example to classify insects based on morphological criteria or describe antibody variation between patients and may not related to the underlying genetic variation of the pathogen or the patient but the history of exposure to different pathogens.

Parimony, distance matrices, maximum likelihood and Bayesian estimation are all methods to produce a phylogeny.