3D space refers to a three-dimensional environment where objects have length, width, and height. This allows for the representation of physical objects as they exist in the real world. In 3D space, points are defined by three coordinates, typically labeled as x, y, and z, which indicate their position along each axis. In various fields like computer graphics, architecture, and virtual reality, 3D space is essential for creating realistic models and simulations. Understanding 3D space helps in visualizing how objects interact and move, making it crucial for design, engineering, and entertainment industries.