Respiratory droplets are tiny liquid particles that are expelled from the mouth or nose when a person talks, coughs, or sneezes. These droplets can vary in size and typically range from 5 to 10 micrometers. They can carry viruses and bacteria, making them a key factor in the spread of infectious diseases, such as the common cold and COVID-19. When someone is infected, respiratory droplets can travel short distances, usually up to about 6 feet, before settling on surfaces or being inhaled by others. This is why maintaining physical distance and wearing masks are important measures to reduce transmission during outbreaks of respiratory illnesses.