A canvas holder is a device used to support a canvas, such as a painting or a photograph. It can be made of different materials and come in various shapes and sizes. The most common types of canvas holders are masts, easels, frames, and tent poles. A MAST is a tall vertical pole that is used to hold up a canvas. An EASEL is a stand with adjustable legs that is used to hold a canvas in an upright position. A FRAME is a rectangular structure that is used to hold a canvas in place. Finally, a tent pole is a long, thin pole that is used to hold up a canvas in a tent-like structure.