Clematis is just about my favorite plant. It is a flowering vine, with literally endless variations. It’s a vigorous grower, and can be easily trained to climb trees, trellises, or along a railing.
The different types indicate their flowering tendencies and their pruning needs- for instance, some clematis are deciduous, and loose their leaves in the winter, while others are evergreen. Some flower seasonally, and other clematis are free-flowering, meaning they create blossoms all year round.
I have two pieces of advice for those interested in adding clematis to their garden. The first is a little line about where to plant them- Top in the Sun, Roots in the Shade. This is crucial because they like cool roots, but require lots of light to bloom profusely. My second tip, look them up! Martha Stewart has a very complete listing of varieties and smart rules for pruning. Be sure to know which pruning group your plants belong to, because some clematis will only flower on their old growth, and over pruning them will hinder their bloom-ability.