Regeneration is the process by which organisms replace or restore lost or damaged tissues, organs, or limbs. This ability varies widely among species; for example, some lizards can regrow their tails, while certain starfish can regenerate entire arms. In more complex organisms, such as humans, regeneration is limited primarily to healing wounds and repairing tissues. In scientific research, understanding regeneration can lead to advancements in medicine, particularly in areas like tissue engineering and stem cell therapy. By studying how different species regenerate, scientists hope to unlock potential treatments for injuries and degenerative diseases in humans, enhancing healing and recovery processes.