Superfluidity is the state that 3He and 4He, isotopes of helium, reach when cooled to 0.0009C and 2.71C above absolute zero, respectively. Superfluids are related to superconductors as they both exhibit quantum properties when their elements are observed at such temperatures.
The defining moment for a superfluid is when its temperature reaches the lambda point on the specific heat capacity vs. temperature graph; at the lambda point the element loses all interaction between atoms, they cease to collide or influence each other, this is where the substance becomes condensed into a superfluidic state. Some examples of this in analysis include the ability for a superfluid to remain completely stationary even as a container that holds it is being rotated, the ability for a superfluid to flow over the walls of an open container, seemingly defying gravity, and to spread out into the thinnest possible state, as to exhibit very little particle stacking.
Superfluids supposedly exist in neutron stars and pulsars, and much theorization has been done to the effect that the pulsar glitches observed are the result of pent eddy release in the cores of such stars. The two superfluidic isotopes are actually very different, 3He is the most often studied and is a fermion (a particle with spin of 1/2) consisting of two elecrons, two protons, and one neutron. 4He, discovered relatively recently is a boson (particle with a spin of any whole integer) quantified by the Bose-Einstein condensation of two helium atoms into one quantum makeup. Basically, the Bose-Einstein condensation process allows particles to disassume all their previously recorded and exhibited characteristics, and like superconductors, take on new characteristic sets described by standard quantum theory. 3He exists in three distinct magneto-temperature phases, designated A, B, and C. These phases are the different ways 3He can exist as a superfluid, altered by their relative temperature, and the magnetic properties of the area they are in. The A state is the most curious, and the state theorized to cause the eddies in the pulsar responsible for its idiosyncracies; in this phase, the superfluid is very highly textured, or anisotropic, and exhibits some of the same characteristics of liquid crystals. In this state, vortices created by spin induced on the textured superfluid have a tendency to model certain quantum phenomena included in topological theory.
Superfluids exhibit the quality of uninterrupted heat transmission, like the electrical conductance shown in superconducting substances. Essentially, they conduct heat as superconductors conduct electricity, without any energy loss. The ideas for application of superconductor technology are widely known, but the heat transmissive qualities of superfluids may be just as awesome as the electrical capabilities of their more well-known brethren.