Fiber cement siding (or "fibre cement cladding" in the UK and Australasia) is a building material used to cover the exterior of a building in both commercial and domestic applications. Fibre cement products came about as a replacement for the widely used "Asbestos Cement Sheeting" product manufactured by "James Hardie" until the late 1980s.
Fibre cement is a composite material made of sand, cement and cellulose fibers. In appearance fibre cement cladding most often consists of overlapping horizontal boards, imitating wooden cladding, clapboard and imitation shingles. Fiber cement siding is also manufactured in a sheet form and is used not only as cladding but is also commonly used as a soffit / eave lining and as a tile underlay on decks and in bathrooms.
Fiber cement cladding is not only used as an exterior cladding, it can also be utilised as a substitute for timber fascias and barge boards in high fire areas. Fibre cement cladding is a very heavy product and requires two people to carry the uncut sheets. Thin fibre cement cladding is fragile before installation and must be handled carefully; it is prone to chipping and breakage if improperly handled.
Source: Wikipedia