The Egyptian cubit is an ancient unit of measurement used in Egypt, primarily for construction and land measurement. It is based on the length of the forearm, from the elbow to the tip of the middle finger, and typically measures about 18 inches (45.72 cm). This unit was crucial for building structures like the Pyramids and temples, ensuring consistency in dimensions. The cubit was often divided into smaller units, such as the handbreadth and fingerbreadth, allowing for more precise measurements. Different variations of the cubit existed, including the royal cubit, which was slightly longer and used for official purposes. This system reflects the advanced understanding of geometry and engineering in ancient Egypt.