Intelligent design is the idea that certain features of the universe and living things are best explained by an intelligent cause rather than random processes. Proponents believe that the complexity and order found in nature, such as the intricate structures of cells or the precise conditions for life on Earth, suggest the involvement of a purposeful designer, rather than just evolution through natural selection. This concept often contrasts with the scientific theory of evolution, which explains the diversity of life through gradual changes over time. Supporters of intelligent design argue that some biological systems, like the human eye or DNA, are too complex to have arisen solely by chance, implying a guiding intelligence behind their existence.