A plant species is a group of plants that share common characteristics and can reproduce with one another. Each species has a unique scientific name, typically consisting of a genus and a specific epithet, such as Rosa rubiginosa for the sweet briar rose. Plant species can vary widely in size, shape, and habitat, ranging from tiny mosses to towering trees. Plant species are essential for maintaining ecosystems and providing resources for humans and wildlife. They play crucial roles in processes like photosynthesis, which produces oxygen, and serve as food and shelter for various organisms. Understanding plant species helps in conservation efforts and sustainable agriculture.