A sanitizer is a substance used to reduce or eliminate harmful microorganisms on surfaces or skin. It often comes in liquid, gel, or foam form and is commonly used in settings like hospitals, restaurants, and homes. Hand sanitizers typically contain alcohol, which is effective in killing germs, while surface sanitizers may contain various chemicals designed for cleaning. Sanitizers are especially important in preventing the spread of infections, particularly during outbreaks of diseases like the flu or COVID-19. They are a convenient alternative when soap and water are not available, making it easier to maintain hygiene in everyday situations.