A brick can be composed of clay-bearing soil, sand, and lime, or concrete materials.
Bricks are produced in numerous classes, types, materials, and sizes which vary with region and time period, and are produced in bulk quantities.
It was at this time in London, that bright red brick was chosen for construction to make the buildings more visible in the heavy fog and to help prevent traffic accidents.
Modern, fired, clay bricks are formed in one of three processes – soft mud, dry press, or extruded.
Depending on the country, either the extruded or soft mud method is the most common, since they are the most economical.
The earliest bricks were dried brick, meaning that they were formed from clay-bearing earth or mud and dried (usually in the sun) until they were strong enough for use.
The oldest discovered bricks, originally made from shaped mud and dating before 7500 BC, were found at Tell Aswad, in the upper Tigris region and in southeast Anatolia close to Diyarbakir.
Bricks were produced on a larger scale under the Western Zhou dynasty about 3,000 years ago, and evidence for some of the first fired bricks ever produced has been discovered in ruins dating back to the Zhou.