A wick is a thin piece of material, often made from cotton or other fibers, that draws liquid fuel up to the flame in a candle or lamp. When the wick is lit, the heat melts the surrounding wax or oil, allowing the fuel to be drawn up and burned, producing light and heat. Wicks are essential components in various lighting devices, including candles, oil lamps, and torches. They come in different sizes and shapes, depending on the type of fuel and the desired burn rate. Proper wick selection is crucial for optimal performance and safety.