Let me clear up a common misconception. When most people say writing in code, what they really mean is writing using a cipher. A code is when a symbol, word, or phrase is used to stand for a different word, phrase, or sentence. A cipher is were each letter in a word is represented with a different letter or symbol.
The dash is a punctuation mark that is similar to a hyphen or minus sign, but differs from both of these symbols primarily in length and function.
The division sign resembles a dash or double dash with a dot above and a dot below (Ã·). It is equivalent to the words divided by.. This symbol is found mainly in arithmetic texts at the elementary-school level. It is rarely used by professional or academic mathematicians, scientists, or engineers.