Burn without a flame is a term used to describe the process of smoldering and glowing. Smoldering is a slow, low-temperature combustion process that occurs without a flame. It is typically used to describe the burning of organic materials such as wood, coal, or tobacco. Glowing is the emission of light from a heated object due to its temperature. This is usually seen in charcoal or other materials that have been heated to a high temperature. Both smoldering and glowing are forms of combustion that occur without a flame.