What makes a egg timers?

An egg timer is a device designed to measure the cooking time for eggs, ensuring they are cooked to the desired level of doneness. Typically, it consists of a simple mechanical or digital timer that can be set for specific durations, often accompanied by a visual or auditory signal when the time is up. Some egg timers are designed to change color based on the temperature of the eggs, indicating soft, medium, or hard boiling. Overall, its primary function is to provide a reliable way to achieve perfect eggs consistently.