We usually represent a thermal or blackbody field as a mixed state in which each mode of the field is in a separate, maximum entropy mixed state represented by a density operator. This is not always the most convenient, nor the most physically enlightening way, however. In my presentation I shall describe (I hope) two very different approaches. The first is based on a pure-state representation, the thermofields, originally designed for application in quantum field theory. This is is especially useful when working with a field described by a continuum as opposed to discrete modes. The second is one based on something closer to classical physics.