Steampunk is a mixture of science fiction, horror, alternate history and fantasy. Often elements of the Victorian era are used when creating mixed media Steampunk projects. This wreath is a fun example of how you can put together something fun and funky to decorate your home in this genre without going all out and hiring a decorator. See the tutorial over at Crafts ‘n Coffee Steampunk craft tutorial: Make a steampunk spring wreath.
More about Steampunk here at Wikipedia