We're all used to flat and sharp signs, also naturals. Accidentals in some cases. But why those unusual signs? I suspect the ♭ may have something to do with the German B, but the ♯ sign? Something to do with the German H? Otherwise known as hash, or, properly 'octothorpe', coined by a telephone company in the '60s. And the natural ♮ seems to almost be a mixture of ♭ and ♯. What's it all about?

  • @Kevin reid - tell us how to make those signs - PLEASE!
    – Tim
    Apr 10, 2017 at 18:11
  • Depends on your computer. I have a Mac, so I open Edit → Emoji & Symbols and type "flat" or "sharp" into the search box. There's also usually some way to type in a numeric code (Unicode or otherwise) for any character if you feel up to memorizing such codes. Wikipedia often mentions the Unicode numbers for particular characters, e.g. sharp.
    – Kevin Reid
    Apr 10, 2017 at 18:16
  • in windows there is a built in program called Character Map which lets you see and copy various ascii symbols. Apr 10, 2017 at 19:04
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    @Tim you can copy them from google from searching "flat sign" or "sharp sign", as long as you're working in a browser/operating system with unicode support (and it appears you are since you can see them). The alt codes for flat, natural and sharp are 9837 9838 and 9839, look at this answer here for how to use them superuser.com/a/1024956/446573
    – Some_Guy
    Apr 11, 2017 at 8:42
  • Why is the 1960s coinage the "proper" name for a symbol that was in standard use (meaning variously "pound" and "number," ignoring the musical sharp symbol) at least a hundred years earlier?
    – phoog
    Aug 30, 2022 at 21:50

2 Answers 2


Medieval German notation for modal music (for all instruments and voices, not just for fretted stringed instruments) was essentially tablature, but using letter names for the notes instead of fret numbers as in modern tab notation. In early modal music, the only "altered" notes were B flat and B natural, which were written using different "square" and "round" shapes of the gothic letter b. These signs were not "accidentals" in the modern sense, but single signs representing the two different pitches of the note. The "square B" later became the gothic letter h, and H is still used in modern German as the name for "B natural" - B means "B flat".

When notation was needed for accidentals on other notes, the "round" or "soft" form of the letter b was used as the sign for a flat, and the "square" form for a sharp.

The original sign for "sharp" was written using diagonal lines, like an x with double strokes. I don't know when or why the "single sharp" became more vertical, and the modern diagonal "double sharp" was first used.

The modern names for "sharp" and "flat" in most European languages (except English) are translations of the German "square B" and "soft/round B".

In early music, there was no great need for a special sign for "natural". Later, the "square b" sign evolved into two different signs for "natural" and "sharp".

Early music notation was not pedantic about for how long an accidental stayed in force (the modern concept of "until the end of the bar" would have made little sense, because bar-lines were not used systematically before the late 16th century). Before the development of a separate "natural" sign, a sharp was used to "cancel" an earlier flat, and vice versa. Traces of this convention were still in use in some of JS Bach's manuscripts (and in some cases were misinterpreted when Bach's music was re-discovered in the 19th mid century), and in some of the examples in his son CPE Bach's book "Essay on the true art of playing keyboard instruments." Even in the 20th-century, one English translation of the "Essay" printed some of these examples (which are nonsensical if interpreted using modern conventions) as they were originally written, with no editorial comment.

This close relationship between "natural" and "sharp" also applied to figured bass. "#" was often used to mean "a major third" even in keys were the intended note was actually a natural. (Modern figured bass notation, used for teaching harmony, tends to be more pedantic about sharps and naturals than when it was a "living" musical notation system.) This usage of "sharp" also survives in modern chord symbols - Ab7#9 doesn't literally mean "play a B sharp!

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    What do you mean by "translations of the German "square B" and "soft/round B" "?
    – Matt L.
    Jul 23, 2016 at 16:25
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    In French, sharp is diese, and flat is bemol, and there seems to be no further translation than that. No reference to anything else, apart from 'bemol' also meaning damper. I can't follow further than that. This answer contains some fascinating stuff. Thanks so far!
    – Tim
    Jul 23, 2016 at 17:03
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    Can you clarify how the Spanish "bemol" and "sostenido" (for flat and sharp resp.) relate to translations of the German "square B" and "soft/round B"? They're nothing alike as far as I can tell, particularly the sharp.
    – E.P.
    Jul 23, 2016 at 20:36
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    Same goes for Italian - diesis (#) and bemolle (b). The German name for the # sign is kreuz; flat sign, b. Funny, but natural is bequadro (becarre in French), both with leanings towards 'square'.
    – Tim
    Jul 24, 2016 at 6:46
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    @E.P In Italian "bemolle" is literally "B molle" i.e. "soft b"; molle means "soft" in Italian. In Spanish there is the derived word "muelle" meaning soft, but they don't say "bemuelle" so it's safe to say it's a loanword from the Italian (or rather, one of the dialects which later became Italian such as venetian or Tuscan) rather than an independent occurrence of "soft B". This would makes sense as Italy was a centre of music, and other terms have also propagated, even into English, such as tempo, crescendo, diminuendo etc. none of which are music specific in Italian.
    – Some_Guy
    Apr 11, 2017 at 8:55

The signs are different forms of the letter B, which were needed as the different hexachords had different types of B's (namely, B flat and B natural). There isn't much more to say, Wikipedia has all you need.

The letter B:

Archaic forms of 'b', the b quadratum (square b, ♮) and b rotundum (round b, ♭) are used in musical notation as the symbols for natural and flat, respectively.


Because B♭ was named by the "soft" or rounded letter B, the hexachord with this note in it was called the hexachordum molle (soft hexachord). Similarly, the hexachord with mi and fa expressed by the notes B♮ and C was called the hexachordum durum (hard hexachord), because the B♮ was represented by a squared-off, or "hard" B. Starting in the 14th century, these three hexachords were extended in order to accommodate the increasing use of signed accidentals on other notes.

History of notation of accidentals:

The different kinds of B were eventually written differently, so as to distinguish them in music theory treatises and in notation. The flat sign ♭ derives from a round b that signified the soft hexachord, hexachordum molle, particularly the presence of B♭. The name of the flat sign in French is bémol from medieval French bé mol which in modern French is bé mou "soft b". The natural sign ♮ and the sharp sign ♯ derive from variations of a square b that signified the hard hexachord, hexachordum durum, where the note in question is B♮. The name of the natural sign in French is bécarre from medieval French bé quarre which in modern French is bé carré "square b". In German music notation the letter B or b always designates B♭ while the letter H or h – a deformation of a square b – designates B♮.

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    Thanks. This seems to address the note B/Bb/H. Why 'soft or hard'? We are given no clues. It doesn't appear to explain the transfer of # and b to the other notes, either. And there seems to be a lot of supposition - 'citation needed'.
    – Tim
    Jul 25, 2016 at 7:04
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    @Tim I don't understand, it's written there. "Soft" and "hard" are the are the names of the B letters, or at least the way by which they were referred. We are given more than a clue. The transfer of # and b to other notes is explained in the rest of the pages, you didn't ask about it, you asked only about the origin of the signs. Read the whole Hexachord page. About the "citation needed", it's just someone who didn't know/bother to add the source, not that the information is doubtful. This mostly repeats the explanation in the Hexachord page anyway. Jul 25, 2016 at 11:37

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