Picornaviridae is a family of small, non-enveloped viruses that have single-stranded RNA as their genetic material. They are known for causing various diseases in humans and animals, including the common cold and polio. The name "picorna" comes from "pico" meaning small and "rna" referring to their RNA genome. These viruses are typically transmitted through the fecal-oral route or respiratory droplets. Picornaviridae includes several important genera, such as Enterovirus, Rhinovirus, and Aphthovirus. Due to their stability in the environment, they can survive outside the host for extended periods, making them highly contagious.