"~" is a symbol commonly known as a tilde. It resembles a wavy line and is often used in various contexts, such as mathematics, computer programming, and linguistics. The tilde has different meanings depending on the field of use. In mathematics, it can represent an approximation or similarity between two values. In computer programming, it is often used to denote home directories or as a bitwise negation operator. Additionally, in Spanish and Portuguese languages, the tilde is used as an accent mark to indicate pronunciation changes in certain letters.