Because there are 12 notes needed in Western music, these 7 notes can have modifiers ("symbols or words that change them"). The two main modifiers are sharps, which raise the pitch a half-step, and flats, which lower the pitch a half-step. The symbol for a sharp is ♯ (like the hash symbol (American: number symbol): #). The symbol for a flat is ♭ (like a lower-case italic "b"). To un-flat or un-sharp a note, the natural symbol, ♮, is written before the note. When writing in words (like this page), the symbols are written after the note name, for example: "B♭" means B flat and "F♯" represents F sharp. However, when writing in music notation, the flat, sharp or natural signs are written BEFORE the note. A way to remember this is to say: if the sign came after the note, it would be too late, and you would have already played it, so it must go before so that you know what is coming.