Concrete is a versatile construction material made from a mixture of cement, water, and aggregates such as sand and gravel. It is known for its strength and durability, making it ideal for a wide range of applications, from sidewalks to skyscrapers. Once poured, concrete hardens over time through a process called hydration, which allows it to gain strength and stability. Its ability to be molded into various shapes and forms makes it a popular choice in modern architecture and infrastructure projects.