"Hardscaping" refers to the non-living components of a landscape. Hardscaping includes elements made from wood, even though wood was once an animate material (in the form of trees). Living plants, by contrast, constitute the "softscaping."
In particular, as the name implies, "hardscaping" refers to hard materials such as those composed of concrete, brick or stone, in addition to wood. For instance, constructing a patio or deck is a hardscaping project, as is a brick walkway, a stone wall, or a wooden fence. But this branch of landscaping goes beyond large-scale projects such as these. Any non-living ornamentation in your landscaping is, technically, part of your hardscaping.
For an overview of masonry hardscaping, please consult Landscaping With Stone.
For more on wood hardscaping projects, please consult The Essential Steps in Building Decks for some problem-solving tips on wood deck design and construction. Also see Building a Garden Arbor for step-by-step instructions for erecting a wooden arbor.
For a fun and easy hardscaping project that will provide your landscaping with a focal point, you can install a water fountain for your garden pond.