Fences serve a variety of purposes, but their main purpose is to enclose an area. Fence sizes can range from just a few feet high to 6 to 10 feet tall for privacy reasons. They also add visual interest and landscaping decoration. A typical fence is built with vertical panels, but many wooden fence styles incorporate horizontally oriented materials. Whether you want to add privacy to your yard, make a hideaway nook in a garden or create a backdrop for a seating area, a horizontal wooden fences can do just that. Horizontal fence styles include post and rail fences, slat board fences and board and wire mesh fences.