Traditional siding material is, of course, wood.  
New applications are increasingly using a
cementuous material such as Hardi-plank or not
rot, it has a 50 year guarantee.  Although it is
slightly more expensive than most wood
shingles its largest disadvantage is a result of it
being much thinner, and as such, much more
flexible than traditional wood planks.  As such, if,
the framing underneath isn't very plum and
uniform, considerable effort will need to be
spent to shim the studs.

Hardi-plank comes in numerous widths from
5.25" (installed 4" to the weather) to 12"
(installed 10.75" to the weather).   Hardi-shingle
comes either in 48" panels (for easy installation -
with a staggered edge, with a straight edge or
with a half-rounded edge) or individual shingles  
(6",8" and 12" wide) for infinite installation

Hardi panels and Hardi trim is also available - so
that window trim and under-eave detail or
column cladding can be executed in
complementary product).

For more information see