A symbol designed for a specific magical purpose is called a sigil. The plural is sigla. Occultists may prefer the anglicized plural "sigils". The term sigil derives from the Latin sigilum meaning "seal." The old norse binding rune is an example of the idea. However, sigla differ from runes as they are designed not to represent an alphabet but are created to form a glyph, composed of a variety of symbols or concepts with the intent and inherent iconic meaning.
A sigil may have an abstract, pictorial or semi-abstract form. It may appear in any medium, physical or virtual, or only in the mind. Visual symbols are the most popular form, but the use of audial and tactile symbols in magic is not unknown.
Austin Osman Spare, in his Zos Kia Cultus, refined the use of sigla by themselves, i.e. outside of ritual. His technique, now known as sigilization, became a core element of chaos magic and from there, has developed into a popular element of western magic.
In a post-modern context businesses may use corporate logos such as the Coca-Cola logo as their sigils and invest them with a comparable degree of prestige or power. The idea that these symbols are consciously used as magical tools is a popular idea among occultists and a common element in conspiracy theories.
