This paper presents some novel interpretations of fusion plasmas which may be of interest to both fission and fusion scientists and engineers. A new fusion ignition parameter (TneτE)I is proposed which is proportional to β2B4 and inversely proportional to the fusion power density (PFusion) of a reacting plasma. Curves are given for many potential nuclear fusion fuels. The energy utilization factor in existing devices is defined as f = PFusion/PLoss = (TneτL)/(TneτE)I; in experimental plasmas, f has increased by about two orders of magnitude in the past decade and now exceeds 10−4 (a "nearest" f* exceeds 10−3). The f factor is also analogous to its fission counterpart in the four-factor neutron multiplication factor k = f η p, where f is the neutron thermal utilization factor. Past, present, and future fusion experiments are discussed briefly in this context.