The two main types of plants are angiosperms and gymnosperms. Angiosperms, also known as flowering plants, are characterized by their production of flowers and seeds enclosed within a fruit. They make up the largest group of plants, with diverse species including grasses, trees, and shrubs. Gymnosperms, on the other hand, are non-flowering plants that produce seeds exposed on cones or in other structures. Examples of gymnosperms include conifers such as pine and spruce trees. Both groups play vital roles in ecosystems, providing oxygen, food, and habitat for various organisms.