Cement is a powdery
substance made by calcining lime and clay, mixed with water to form a paste
that hardens over time. It's a key ingredient in concrete, mortar, and plaster.
When mixed with aggregates such as sand and gravel, cement forms concrete, which
is widely used in construction for buildings, bridges, roads, and other
infrastructure projects. Cement provides the binding agent that holds these
materials together, giving them strength and durability.