Switch knives, also known as switchblades or automatic knives, are a type of folding knife with a spring-loaded blade that can be deployed quickly with the press of a button or switch. Synonyms for switch knives could include phrases like "automatic folding knives," "spring-assisted knives," "push-button knives," or "rapid-deployment knives." The legality of switch knives can vary by location, and it's important to check local laws before carrying or using these types of knives. While switch knives may have a reputation as only being used by criminals, they can also be a useful tool for individuals who need to quickly open and use a knife in a variety of situations.