Define the term "aggregate" in the context of concrete.

The term "aggregate" in the context of concrete refers to the granular materials that are utilized to create concrete mixes. Aggregates serve as the primary structural component, providing strength and volume to the concrete. They can be classified into two categories: coarse aggregates, such as gravel or crushed stone, and fine aggregates, like sand. The proportions and types of aggregates used significantly influence the concrete's properties, including workability, strength, and durability.

Using aggregates is essential because they help reduce the cost of concrete by providing bulk without significantly affecting the mixture's overall performance. Proper selection and grading of aggregates are vital for achieving desired characteristics in the final concrete product, making it a crucial aspect of concrete technology and construction practices.