Replacement refers to the act of substituting one item, person, or concept for another. This can occur in various contexts, such as replacing a broken light bulb with a new one, or swapping out an old computer for a newer model. The goal of replacement is often to restore functionality or improve performance. In many cases, replacement is necessary for maintenance and efficiency. For example, in sports, a player may be replaced due to injury, allowing another athlete to take their place. Similarly, in manufacturing, outdated machinery may be replaced to enhance productivity and reduce costs.