Editing Musical note (section)

=== Accidentals ===
{{Main article|Accidental (music)}}

Notes that belong to the [[diatonic scale]] relevant in a [[Tonality|tonal]] context are called ''[[diatonic]] notes''. Notes that do not meet that criterion are called ''[[chromatic]] notes'' or ''[[accidentals]]''. Accidental symbols visually communicate a modification of a note's pitch from its tonal context. Most commonly,{{NoteTag|Another style of notation, rarely used in English, uses the suffix "is" to indicate a sharp and "es" (only "s" after A and E) for a flat (e.g. Fis for F♯, Ges for G♭, Es for E♭). This system first arose in Germany and is used in almost all European countries whose main language is not English, Greek, or a Romance language (such as French, Portuguese, Spanish, Italian, and Romanian).

In most countries using these suffixes, the letter H is used to represent what is B natural in English, the letter B is used instead of B♭, and Heses (i.e., H𝄫) is used instead of B𝄫 (although Bes and Heses both denote the English B𝄫). Dutch-speakers in Belgium and the Netherlands use the same suffixes, but applied throughout to the notes A to G, so that B, B♭ and B have the same meaning as in English, although they are called B, Bes, and Beses instead of B, B flat and B double flat. Denmark also uses H, but uses Bes instead of Heses for B𝄫.}} the [[sharp (music)|sharp]] symbol ({{music|sharp}}) raises a note by a [[half step]], while the [[flat (music)|flat]] symbol ({{music|flat}}) lowers a note by a half step. This half step [[Interval (music)|interval]] is also known as a [[semitone]] (which has an [[equal temperament]] frequency ratio of [[Twelfth root of two|{{radic|2|12}}]]&nbsp;≅&nbsp;1.0595). The [[natural (music)|natural]] symbol ({{music|natural}}) indicates that any previously applied accidentals should be cancelled. Advanced musicians use the [[Sharp (music)|double-sharp]] symbol ({{music|##}}) to raise the pitch by two [[semitone]]s, the [[Flat (music)|double-flat]] symbol ({{music|bb}}) to lower it by two semitones, and even more advanced accidental symbols (e.g. for [[quarter tone]]s). Accidental symbols are placed to ''the right'' of a note's letter when written in text (e.g. F{{music|sharp}} is [[F♯ (musical note)|F-sharp]], B{{music|flat}} is [[B♭ (musical note)|B-flat]], and C{{music|natural}} is [[Diatonic scale|C natural]]), but are placed to ''the left'' of a [[notehead|note's head]] when drawn on a [[Staff (music)|staff]].

Systematic alterations to any of the 7 lettered [[pitch classes]] are communicated using a [[key signature]]. When drawn on a staff, accidental symbols are positioned in a key signature to indicate that those alterations apply to all occurrences of the lettered pitch class corresponding to each symbol's position. Additional explicitly-noted accidentals can be drawn next to noteheads to override the key signature for all subsequent notes with the same lettered pitch class in that [[Bar (music)|bar]]. However, this effect does not accumulate for subsequent accidental symbols for the same pitch class.