This document provides an introduction and overview of cryptogams, which are non-seed bearing plants that reproduce through spores. Cryptogams are divided into lower plants that reproduce vegetatively and sexually through various types of spores and gametes. They undergo alternation of generations, with a sporophytic phase involving asexual reproduction and a gametophytic phase involving sexual reproduction. Cryptogams are further divided into three main groups: Thallophyta, Bryophyta, and Pteridophytes. The document also briefly discusses phanerogams, or seed-bearing plants like angiosperms and gymnosperms, and how they differ from cryptogams.