This document provides an overview of concrete, including its definition, composition, properties, speciality types, famous structures made of concrete, and world records. Concrete is composed of coarse aggregate bonded together with a cement that hardens over time. It discusses the main ingredients of concrete including aggregates, cement, water, and reinforcement. Specialty concretes described include nanoconcrete, microbial concrete, and polymer concrete. Famous concrete structures highlighted are the Three Gorges Dam, Petronas Towers, and Burj Khalifa. World records listed include the largest single concrete pour for the Three Gorges Dam and records for concrete pumping and underwater placement.