Courtesy: PrecisionCraft Log and Timber Homes
Wikipedia has a nice introduction to timber framing...
"Timber framing and "post-and-beam" construction is a general term for building with heavy timbers rather than "dimension lumber" such as 2"x4"s. Traditional timber framing is the method of creating structures using heavy squared off and carefully fitted and joined timbers with joints secured by large wooden pegs (larger versions of the mortise and tenon joints in furniture). It is commonplace in wooden buildings from the 19th century and earlier. The method comes from making things out of logs and tree trunks without modern high tech saws to cut lumber from the starting material stock. Using axes, adzes and draw knives, hand powered auger drill bits (bit and brace), and laborious woodworking, artisans or farmers could gradually assemble a building capable of bearing heavy weight without excessive use of interior space given over to vertical support posts. Since this building method has been used for thousands of years in many parts of the world their are many styles of historic framing. These styles are often categorized by the type of foundation, walls, how and where the beams intersect, the use of curved timbers, and the roof framing details. Three basic types of timber frames in English speaking countries are the box frame, Cruck frame, and aisled frame."
If you're interested and want to take on a new dream, check out the website of the Timber Frame Business Council, headquartered in Gettysburg, PA. Warning, though...timber frame dreaming is highly contagious.