Instrumentation of Romantic period music featured
A. parts for wind and brass instruments doubling
with the string parts.
B. complete orchestration, with unique parts written
for the different sections of the orchestra.
C. parts for strings and harpsichords but no parts
for wind or brass instruments.

relief sculpture - images are set against a flat background.

a coin is a good example: the inscription, the date, and the figure are slightly raised above a flat surface. the ancient egyptians sometimes carved figures into a flat surface.  

pro: they take significantly less time to make and do not require as much tools or skills as free-standing

cons: not nearly as realistic, as it is not fully 3-d, and does not have the details that a free-standing one does.

freestanding sculptures (also called  carved in the round) are not attached to any  background.   they are 3-dimensional  and fully rendered.