Tightwire is the skill of maintaining balance while walking along a tensioned wire between two points. It can be done either using a balancing tool (umbrella, fan, balance pole, etc.) or "freehand", using only one's body to maintain balance. Typically, tightwire performances either include dance or object manipulation. Object manipulation acts include a variety of props in their acts, such as clubs, rings, hats, or canes. Tightwire performers have even used wheelbarrows with passengers, ladders, and animals in their act. The technique to maintain balance is to keep the performer's centre of mass above their support point—usually their feet.