Mosses, ferns and liverworts are all primitive plants that do not produce flowers or seeds. Instead, these plants produce sexually through spores and asexually by creating clones of themselves. While ferns are somewhat more advanced and have a true vascular system, mosses and liverworts do not have a vascular system.
Without vascular systems, mosses and liverworts are limited to very damp environments. Ferns, which have roots and vascular systems, can successfully live in drier habitats. Additionally, according to the University of Cincinnati, most ferns have underground stems, which are called rhizomes. Some have vertically growing stems and often go by the common name "tree ferns," based on their growth habit.