Q

Depending on the typeface used to typeset the letter Q, the letter's tail may either bisect its bowl as in Helvetica,[15] meet the bowl as in Univers, or lie completely outside the bowl as in PT Sans. In writing block letters, bisecting tails are fastest to write, as they require less precision. All three styles are considered equally valid, with most serif typefaces having a Q with a tail that meets the circle, while sans-serif typefaces are more equally split between those with bisecting tails and those without.[16] Typefaces with a disconnected Q tail, while uncommon, have existed since at least 1529.[17] A common method among typographers to create the shape of the Q is by simply adding a tail to the letter O.[16][18][19]

Old-style serif fonts, such as Garamond, may contain two capital Qs: one with a short tail to be used in short words, and another with a long tail to be used in long words.[17] Some early metal type fonts included up to 3 different Qs: a short-tailed Q, a long-tailed Q, and a long-tailed Q-u ligature.[14] This print tradition was alive and well until the 19th century, when long-tailed Qs fell out of favor: even recreations of classic typefaces such as Caslon began being distributed with only short Q tails.[20][14] Not a fan of long-tailed Qs, American typographer D. B. Updike celebrated their demise in his 1922 book Printing Types, claiming that Renaissance printers made their Q tails longer and longer simply to "outdo each other".[14] Latin-language words, which are much more likely than English words to contain "Q" as their first letter, have also been cited as the reason for their existence.[14] The long-tailed Q had fallen completely out of use with the advent of early digital typography, as many early digital fonts could not choose different glyphs based on the word that the glyph was in, but it has seen something of a comeback with the advent of OpenType fonts and LaTeX, both of which can automatically typeset the long-tailed Q when it is called for and the short-tailed Q when not.[21][22]

Owing to the allowable variation in the Q, the letter is a very distinctive feature of a typeface;[16][23] like the ampersand, the Q is cited as a letter that gives typographers a chance to express themselves.[4]

Identifont, an automated typeface identification service that identifies typefaces by questions about their appearance, asks about the Q tail second if the "sans-serif" option is chosen.[24] Out of Identifont's database, Q tails are divided thus:[25]

Q tail type	Serif	Sans-serif
Bisecting	1461	2719
Meets bowl	3363	4521
Outside bowl	271	397
"2" (${\displaystyle {\mathcal {Q}}}$) shape	304	428
Inside bowl	129	220
Total	5528	8285

Some typographers prefer one "Q" design over another: Adrian Frutiger, famous for the airport typeface that bears his name, remarked that most of his typefaces feature a Q tail that meets the bowl and then extends horizontally.[19] Frutiger considered such Qs to make for more "harmonious" and "gentle" typefaces.[19] Some typographers, such as Sophie Elinor Brown, have listed "Q" as being among their favorite letters.[26][27]

A comparison of the glyphs of ⟨q⟩ and ⟨g⟩

The lowercase "q" is usually seen as a lowercase "o" or "c" with a descender (i.e., downward vertical tail) extending from the right side of the bowl, with or without a swash (i.e., flourish), or even a reversed lowercase p. The "q"'s descender is usually typed without a swash due to the major style difference typically seen between the descenders of the "g" (a loop) and "q" (vertical). When handwritten, or as part of a handwriting font, the descender of the "q" sometimes finishes with a rightward swash to distinguish it from the letter "g" (or, particularly in mathematics, the digit "9").

The International Phonetic Alphabet uses ⟨q⟩ for the voiceless uvular stop.

In English, the digraph ⟨qu⟩ most often denotes the cluster /kw/; however, in borrowings from French, it represents /k/, as in 'plaque'. See the list of English words containing Q not followed by U. Q is the second least frequently used letter in the English language (after Z), with a frequency of just 0.1% in words. Q has the third fewest English words where it is the first letter, after Z and X.

In most European languages written in the Latin script, such as in Romance and Germanic languages, ⟨q⟩ appears almost exclusively in the digraph ⟨qu⟩. In French, Occitan, Catalan and Portuguese, ⟨qu⟩ represents /k/ or /kw/; in Spanish, it represents /k/. ⟨qu⟩ replaces ⟨c⟩ for /k/ before front vowels ⟨i⟩ and ⟨e⟩, since in those languages ⟨c⟩ represents a fricative or affricate before front vowels. In Italian ⟨qu⟩ represents [kw] (where [w] is the semivowel allophone of /u/).

It is not considered to be part of the Cornish (Standard Written Form), Estonian, Icelandic, Irish, Latvian, Lithuanian, Serbo-Croatian, Scottish Gaelic, Slovenian, Turkish, or Welsh alphabets.

⟨q⟩ has a wide variety of other pronunciations in some European languages and in non-European languages that have adopted the Latin alphabet.

• Q with diacritics: ʠ Ɋ ɋ q̃
• Small capital q: ꞯ (Used in Japanese linguistics[29])
• Gha: Ƣ ƣ

• 𐤒 : Semitic letter Qoph, from which the following symbols originally derive
  • Ϙ ϙ: Greek letter Koppa
    • 𐌒 : Old Italic Q, which is the ancestor of modern Latin Q
    • Ԛ ԛ : Cyrillic letter Qa

• ℺ : rotated capital Q, a signature mark
• Ꝗ ꝗ, Ꝙ ꝙ : Various forms of Q were used for medieval scribal abbreviations[30]