  We review investigations on defects in systems described by real scalar
fields in (D,1) space-time dimensions. We first work in one spatial dimension,
with models described by one and two real scalar fields, and in higher
dimensions. We show that when the potential assumes specific form, there are
models which support stable global defects for D arbitrary. We also show how to
find first-order differential equations that solve the equations of motion, and
how to solve models in D dimensions via soluble problems in D=1. We illustrate
the procedure examining specific models and showing how they may be used in
applications in different contexts in condensed matter physics, and in other
areas.
