Nano silver refers to extremely small particles of silver that are typically between 1 and 100 nanometers in size. These particles are so small that they are measured in nanometers, which are one billionth of a meter. Nano silver is often produced through a process called "nanoparticle synthesis," which involves breaking down larger particles of silver into smaller ones. Nano silver is known for its antibacterial, antiviral, and antifungal properties, making it useful in a variety of applications including wound healing, water treatment, and various medical treatments. However, the safety and efficacy of nano silver are still being studied and debated, and it should be used with caution and under the guidance of a medical professional.