Cinder block
The Breezeblock is also a radio show on BBC Radio 1.
A cinder block, also called a breeze block, is a rectangular concrete block used in construction. Cinder blocks are typically in the shape of two squares joined on one side to form a rectangle, with the insides of the squares hollow. This allows structures to be built in the traditional masonry style of overlapping rows, with the structure's weight carried by the "walls" of the blocks.
Cinder block is a very common building material for the foundations and load bearing parts of buildings. Suburban houses with a basement typically employ a concrete slab with a cinder block wall on the perimeter. Large buildings typically use copious amounts of cider block; for even larger buildings, cinder block supplements steel I-beams. Since cinder block is not particularly sightly, it is usually covered with stucco, brick, paint or siding. The holes inside cinder block allow rebar and reinforcing concrete (creating reinforced concrete) to run vertically through the block to compensate for the lack of tensile strength.
Originally, blocks called clinker blocks were used, which were made from a mixture of clinker, from boilers and furnaces, and cement. Clinker blocks were typically manufactured close to power plants and other producers of furnace byproducts. Clinker blocks crumbled easily and were abandoned for the modern cinder block.