Fission is the process of splitting an atom using a neutron. Such processes are done with heavy (uranium, plutonium, etc.) radioactive elements. The first fission bomb was detonated July 16, 1945 at White Sands Missile Range in New Mexico.
A fusion reaction occurs when light elements (hydrogen) are forced together to create a heavier atom. Isotopes of hydrogen, deuterium and tritium, are combined to create a helium atom with the release of a 14-Mev neutron.
For more information about fusion and how it would be accomplished in a z-pinch pulsed power facility, check out the pdfs below.
HEDP or High-Energy-Density Physics is the study of materials brought to extreme conditions of temperature and density. Development of an understanding of materials under such conditions requires information about the intrinsic state of the material itself (e.g., atomic physics, opacity, phase and material strength, and equation of state), as well as an understanding of the evolution of the material under external forces (hydrodynamics and radiation transport). In general, high-energy-density physics problems are particularly complex because a system can often evolve to a turbulent, non-linear state in which all correlations to initial conditions and driving forces are lost.
ICF or Inertial Confinement Fusion is a method that attempts to heat fusion fuel, such as deuterium-tritium, to thermonuclear temperatures so fast that an appreciable number of fusion reactions occur before it is blown apart (i.e., explosively disassembles).
An Isotope, if not a baseball player, is one of two or more atoms with the same atomic number but with different numbers of neutrons.