  We present an extensive but concise review of our present understanding,
largely based on theory and simulation work from our group, on the equilibrium
behavior of solid surfaces and nanosystems close to the bulk melting point. In
the first part we define phenomena, in particular surface melting and
nonmelting, and review some related theoretical approaches, from heuristic
theories to computer simulation. In the second part we describe the surface
melting/nonmelting behavior of several different classes of solids, ranging
from van der Waals crystals, to valence semiconductors, to ionic crystals and
metals. In the third part, we address special cases such as strained solids,
the defreezing of glass surfaces, and rotational surface melting. Next, we
digress briefly to surface layering of a liquid metal, possibly leading to
solid-like or hexatic two dimensional phases floating on the liquid. In the
final part, the relationship of surface melting to the premelting of
nanoclusters and nanowires is reviewed.
