Ferns might be my favorite plant unless it is summer and I am near a prairie. They are considered among the most 'primitive' of plants, yet their diversity of form and size and shape and color is awesome. All have some basic characteristics in common though.
1) They are not flowering plants: Their reproduction process begins with spores. They require a humid environment, due to the complex two phase reproductive process. Ferns as we know them make spores. Tiny new plants grow from spores, and this second stage plant makes eggs and sperm. The sperm requires water to swim to the egg of another tiny plant. That fertilized egg grows right there inside the tiny plant as it shrivels away, to make the fern plants that we know. This need for water on the surfaces where ferns live for the fern sperm to swim in makes Garfield Park Conservatory's fern greenhouse have the most the most humid tropical feeling of all of them.
2) Ferns have leaves that grow radially from a central stem, with most having a long lance shaped leaf. Some have strap like leaves and in others, that strap is divided or double divided into a lacey pattern. And the leaves unfurl from the central point in the shape of a curl that is called a fiddlehead, to the joy of my fiddle playing oldest son. It has been one of our traditions while in the fern room of the Garfield Park Conservatory to hunt for fiddleheads.