A sigil is a symbol used in some programming languages to indicate different program features. BASIC and Perl are two of the most popular languages to use sigils. Typically, the sigil initializes a variable, collection of variables, collection of characters, or string. In BASIC, for example, the sigil $ indicates a variable with a string.
In Elixir, sigils can introduce different elements in programming: ~s initializes a string, while ~S initializes a raw string literal (which does not allow escapes). ~w is used to separate a list of words:
~w (word word word)