Concrete entities are physical objects or beings that can be perceived through the senses. They have a definite shape, size, and presence in the real world. Examples of concrete entities include trees, cars, and people. These entities can be observed, touched, and interacted with, making them distinct from abstract concepts. In contrast to abstract entities, which represent ideas or qualities, concrete entities exist in a tangible form. They play a crucial role in our daily lives, as they are the building blocks of our environment. Understanding concrete entities helps us navigate and make sense of the world around us.