Its use to denote division is not recommended in the ISO 80000-2 standard for mathematical notation.
[1] The obelus, a historical glyph consisting of a horizontal line with (or without) one or more dots, was first used as a symbol for division in 1659, in the algebra book Teutsche Algebra by Johann Rahn, although previous writers had used the same symbol for subtraction.
[2] Some near-contemporaries believed that John Pell, who edited the book, may have been responsible for this use of the symbol.
[1] In Italy, Poland and Russia, the ÷ sign was sometimes used to denote a range of values, and in Scandinavian countries it was, and sometimes still is, used as a negation sign:[5] the Unicode Consortium has allocated a separate code point, U+2052 ⁒ COMMERCIAL MINUS SIGN for this usage uniquely;[6][7] the exact form of the symbol displayed is typeface (font) dependent.
The symbol was assigned to code point 0xF7 in ISO 8859-1, as the "division sign".