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This article is about the eighteenth letter of the Latin alphabet. For the reversed version, see Я. For other uses, see R [disambiguation].

"ℛ" redirects here. For the Unicode block containing this character, see Letterlike Symbols.

RR rUsageWriting systemLatin scriptTypeAlphabetic and LogographicLanguage of originLatin languagePhonetic usage[r] [ɾ] [ɹ] [ɻ] [ɺ] [ʀ] [ʁ] [ɽ] [] [English variations] Unicode codepoint`U+0052, U+0072`Alphabetical position18HistoryDevelopment

• • • Ρ ρ
      • 𐌓
        • • • • R r Time period~50 to presentDescendants • ℟ • ℞ • ® • Ɍ • ᚱ • 𐍂 • ᎡSisters • Р • ר • ر • ܪ • ࠓ • 𐎗 • 𐡓 • ረ • Ռ • ռ • Ր • ր • ર • रOtherOther letters commonly used with, rhWriting directionLeft-to-RightThis article contains phonetic transcriptions in the International Phonetic Alphabet [IPA]. For an introductory guide on IPA symbols, see Help:IPA. For the distinction between [ ], / / and ⟨ ⟩, see .

R, or r, is the eighteenth letter of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is [pronounced ], plural ars, or in Ireland or . In some varieties of African-American Vernacular English, the name of the letter is pronounced as "arruh" [pronounced /ɑɹːə/].

The letter ⟨r⟩ is the eighth most common letter in English and the fourth-most common consonant [after ⟨t⟩, ⟨n⟩, and ⟨s⟩].

The letter ⟨r⟩ is used to form the ending "-re", which is used in certain words such as centre in some varieties of English spelling, such as British English. Canadian English also uses the "-re" ending, unlike American English, where the ending is usually replaced by "-er" [center]. This does not affect pronunciation.

Name[edit]

The name of the letter in Latin was er [/ɛr/], following the pattern of other letters representing continuants, such as F, L, M, N and S. This name is preserved in French and many other languages. In Middle English, the name of the letter changed from /ɛr/ to /ar/, following a pattern exhibited in many other words such as farm [compare French ferme] and star [compare German Stern].

In Hiberno-English the letter is called /ɒr/ or /ɔːr/, somewhat similar to oar, ore, orr.

The letter R is sometimes referred to as the littera canīna [literally 'canine letter', often rendered in English as the dog's letter]. This Latin term referred to the Latin R that was trilled to sound like a growling dog, a spoken style referred to as vōx canīna ['dog voice']. A good example of a trilled R is in the Spanish word for dog, perro.

In William Shakespeare's Romeo and Juliet, such a reference is made by Juliet's nurse in Act 2, scene 4, when she calls the letter R "the dog's name". The reference is also found in Ben Jonson's English Grammar.

History[edit]

Antiquity[edit]

The word prognatus as written on the Sarcophagus of Lucius Cornelius Scipio Barbatus [280 BC] reveals the full development of the Latin R by that time; the letter P at the same time still retains its archaic shape distinguishing it from Greek or Old Italic rho.

The letter R is believed to derive ultimately from an image of a head, used in Semitic alphabets for the sound /r/ because the word for "head" was rêš [or similar] in most Semitic languages. The word became the name of the letter, as an example of acrophony.

It developed into Greek 'Ρ' ῥῶ [rhô] and Latin R. The descending diagonal stroke develops as a graphic variant in some Western Greek alphabets [writing rho as

], but it was not adopted in most Old Italic alphabets; most Old Italic alphabets show variants of their rho between a "P" and a "D" shape, but without the Western Greek descending stroke. Indeed, the oldest known forms of the Latin alphabet itself of the 7th to 6th centuries BC, in the Duenos and the Forum inscription, still write r using the "P" shape of the letter. The Lapis Satricanus inscription shows the form of the Latin alphabet around 500 BC. Here, the rounded, closing Π shape of the p and the Ρ shape of the r have become difficult to distinguish. The descending stroke of the Latin letter R has fully developed by the 3rd century BC, as seen in the Tomb of the Scipios sarcophagus inscriptions of that era. From around 50 AD, the letter P would be written with its loop fully closed, assuming the shape formerly taken by R.

Cursive[edit]

18th-century example of use of r rotunda in English blackletter typographyLetter R from the alphabet by Luca Pacioli, in De divina proportione [1509]

The minuscule [lowercase] form [r] developed through several variations on the capital form. Along with Latin minuscule writing in general, it developed ultimately from Roman cursive via the uncial script of Late Antiquity into the Carolingian minuscule of the 9th century.

In handwriting, it was common not to close the bottom of the loop but continue into the leg, saving an extra pen stroke. The loop-leg stroke shortened into the simple arc used in the Carolingian minuscule and until today.

A calligraphic minuscule r, known as r rotunda [ꝛ], was used in the sequence or, bending the shape of the r to accommodate the bulge of the o [as in oꝛ as opposed to or]. Later, the same variant was also used where r followed other lower case letters with a rounded loop towards the right [such as b, h, p] and to write the geminate rr [as ꝛꝛ]. Use of r rotunda was mostly tied to blackletter typefaces, and the glyph fell out of use along with blackletter fonts in English language contexts mostly by the 18th century.

Insular script used a minuscule which retained two downward strokes, but which did not close the loop ["Insular r", ꞃ]; this variant survives in the Gaelic type popular in Ireland until the mid-20th century [but now mostly limited to decorative purposes].

Pronunciation and use[edit]

Pronunciations of Rr Languages in italics do not use the roman alphabet; the table refers to romanizations Language Dialect[s] Pronunciation [IPA] Environment Notes Albanian/ɾ/rr represents a trilled /r/ Arabic Most dialects/r/North Mesopotamian, Judeo-Iraqi/ʀ/Egyptian/ɾ/Aragonese/r/Word-initially/ɾ/Usually rr represents a trilled /r/Asturian/r/Word-initially/ɾ/Usually rr represents a trilled /r/Basque/r/Word-initially/ɾ/Usually rr represents a trilled /r/Catalan/r/Word-initially/ɾ/Usually Danish/ʀ/ /r/Archaic Dutch Most dialects/ɾ/Brabantish, Limburgish/ʀ/English Non-rhotic/ɹ̠/Before vowels silent After vowels Rhotic/ɻ/Before vowels ʵ After vowels Esperanto/ɾ/Faroese/ɹ/French/ʁ/Galician/ɾ/German Standard/ʀ/Before vowels/ɐ̯/After vowels Gutnish/ɻ/Haitian/ɣ/Hebrew/ʁ/ /r/Archaic Hopi/ʐ/Indonesian Standard/r/Sumatran dialects/r/Before vowels/consonants silent After vowels Irish/ɾ/ /ɻʲ/After i; before e, i Italian/r/Japanese Standard/ɾ/Leonese/ɾ/Malay Standard/r/Before vowels/consonants silent After vowels Mandarin Standard/ʐ/Manx/ɹ/silent Māori/ɾ/Norwegian Most dialects/r/Western and Southern dialects/ʁ/Tromsø/ʐ/Portuguese/ʁ/In certain environments/ɾ/In certain environments Scottish Gaelic/ɾ/Usually/ɾʲ/After i; before e, i Sicilian/ɹ/Spanish Some dialects/l/After a vowel Most dialects/r/Word-initially All dialects/ɾ/Usually Puerto Rican/ʁ/Word-initially Swedish Most dialects/ɾ/Southern dialects/ʀ/Turkish/ɾ/Venetian Most dialects/ɾ/Venice/ʀ/Vietnamese Northern dialect/z/Most dialects/ʐ/, /ɾ/, /r/, /ɹ/

Non-English languages[edit]

⟨r⟩ represents a rhotic consonant in many languages, as shown in the table below.

Alveolar trill [r]Listen some dialects of British English or in emphatic speech, standard Dutch, Estonian, Finnish, Galician, German in some dialects, Hungarian, Icelandic, Indonesian, Italian, Czech, Javanese, Lithuanian, Latvian, Latin, Norwegian mostly in the northwest, Polish, Portuguese [traditional form], Romanian, Russian, Scots, Slovak, Swedish, Sundanese, Ukrainian, Welsh; also Catalan, Spanish and Albanian ⟨rr⟩Alveolar approximant [ɹ]Listen English [most varieties], Dutch in some Netherlandic dialects [in specific positions of words], Faroese, Sicilian Alveolar flap / Alveolar tap [ɾ]Listen Portuguese, Catalan, Spanish and Albanian ⟨r⟩, Turkish, Dutch, Italian, Venetian, Galician, Leonese, Norwegian, Irish, Māori Voiced retroflex fricative [ʐ]Listen Norwegian around Tromsø; Spanish used as an allophone of /r/ in some South American accents; Hopi used before vowels, as in raana, "toad", from Spanish rana; Hanyu Pinyin transliteration of Standard Chinese. Retroflex approximant [ɻ]Listen some English dialects [in the United States, South West England, and Dublin], Gutnish Retroflex flap [ɽ]Listen Norwegian when followed by , sometimes in Scottish English Uvular trill [ʀ]Listen German stage standard; some Dutch dialects [in Brabant and Limburg, and some city dialects in The Netherlands], Swedish in Southern Sweden, Norwegian in western and southern parts, Venetian only in Venice area. Voiced uvular fricative [ʁ]Listen North Mesopotamian Arabic, Judeo-Iraqi Arabic, German, Danish, French, standard European Portuguese ⟨rr⟩, standard Brazilian Portuguese ⟨rr⟩, Puerto Rican Spanish ⟨rr⟩ and 'r-' in western parts, Norwegian in western and southern parts.

Other languages may use the letter ⟨r⟩ in their alphabets [or Latin transliterations schemes] to represent rhotic consonants different from the alveolar trill. In Haitian Creole, it represents a sound so weak that it is often written interchangeably with ⟨w⟩, e.g. 'Kweyol' for 'Kreyol'.

Brazilian Portuguese has a great number of allophones of /ʁ/ such as [χ], [h], [ɦ], [x], [ɣ], [ɹ] and [r], the latter three ones can be used only in certain contexts [[ɣ] and [r] as ⟨rr⟩; [ɹ] in the syllable coda, as an allophone of /ɾ/ according to the European Portuguese norm and /ʁ/ according to the Brazilian Portuguese norm]. Usually at least two of them are present in a single dialect, such as Rio de Janeiro's [ʁ], [χ], [ɦ] and, for a few speakers, [ɣ].

Other systems[edit]

The International Phonetic Alphabet uses several variations of the letter to represent the different rhotic consonants; ⟨r⟩ represents the alveolar trill.

[edit]

Descendants and related characters in the Latin alphabet[edit]

• R with diacritics: Ŕ ŕ Ɍ ɍ Ř ř Ŗ ŗ Ṙ ṙ Ȑ ȑ Ȓ ȓ Ṛ ṛ Ṝ ṝ Ṟ ṟ Ꞧ ꞧ Ɽ ɽ R̃ r̃ ᵲ ꭨ ᵳ ᶉ
• International Phonetic Alphabet-specific symbols related to R: 𝼈 ɹ ɺ ɾ ɻ ɽ ʀ ʁ ʶ ˞ ʴ
• : 𐞦 𐞧 𐞨 𐞩 𐞪
• Obsolete and nonstandard symbols in the International Phonetic Alphabet: ɼ ɿ
• Uralic Phonetic Alphabet-specific symbols related to R:
  • U+1D19 ᴙ LATIN LETTER SMALL CAPITAL REVERSED R
  • U+1D1A ᴚ LATIN LETTER SMALL CAPITAL TURNED R
  • U+1D3F ᴿ MODIFIER LETTER CAPITAL R
  • U+1D63 ᵣ LATIN SUBSCRIPT SMALL LETTER R
• Teuthonista phonetic transcription-specific symbols related to R:
  • U+AB45 ꭅ LATIN SMALL LETTER STIRRUP R
  • U+AB46 ꭆ LATIN LETTER SMALL CAPITAL R WITH RIGHT LEG
• Anthropos phonetic transcription:
  • U+AB48 ꭈ LATIN SMALL LETTER DOUBLE R
  • U+AB49 ꭉ LATIN SMALL LETTER R WITH CROSSED-TAIL
  • U+AB4A ꭊ LATIN SMALL LETTER DOUBLE R WITH CROSSED-TAIL
• Otto Bremer's phonetic transcription:
  • U+AB47 ꭇ LATIN SMALL LETTER R WITHOUT HANDLE
  • U+AB4B ꭋ LATIN SMALL LETTER SCRIPT R
  • U+AB4C ꭌ LATIN SMALL LETTER SCRIPT R WITH RING
• 𝼨 : R with mid-height left hook was used by the British and Foreign Bible Society in the early 20th century for romanization of the Malayalam language.
• ⱹ : Turned r with tail is used in the Swedish Dialect Alphabet
• Other variations of R used for phonetic transcription: 𝼕 𝼖 ʳ ʵ

Calligraphic variants in the Latin alphabet[edit]

• Ꝛ ꝛ : R rotunda
• Ꞃ ꞃ : "Insular" R [Gaelic type]
• ᫍ : Combining insular r was used in the Ormulum

Ancestors and siblings in other alphabets[edit]

• 𐤓 : Semitic letter Resh, from which the following letters derive
  • Ρ ρ : Greek letter Rho, from which the following letters derive
    • 𐌓 : Old Italic letter R, the ancestor of modern Latin R
      • ᚱ : Runic letter Raido
    • Р р : Cyrillic letter Er
    • 𐍂 : Gothic letter Reda

Abbreviations, signs and symbols[edit]

• ℟ : symbol for "response" in liturgy
• ℞ : Medical prescription Rx
• ® : Registered trademark symbol
• ₹ : Indian rupee sign

Encoding[edit]

Character information Preview R r Unicode name LATIN CAPITAL LETTER R LATIN SMALL LETTER R Encodings decimal hex dec hex Unicode 82 U+0052 114 U+0072 UTF-8 82 52 114 72 Numeric character reference &

82; &

x52; &

114; &

x72; EBCDIC family 217 D9 153 99 ASCII 1 82 52 114 72 1 Also for encodings based on ASCII, including the DOS, Windows, ISO-8859 and Macintosh families of encodings.

What is R used for?

R is widely used in data science by statisticians and data miners for data analysis and the development of statistical software. R is one of the most comprehensive statistical programming languages available, capable of handling everything from data manipulation and visualization to statistical analysis.

What is the Web version of R?

WebR is a version of the statistical language R compiled for the browser and Node. js using WebAssembly, via Emscripten. WebR makes it possible to run R code in the browser without the need for an R server to execute the code: the R interpreter runs directly on the user's machine.

What is the meaning of Cran in R?

Comprehensive R Archive Network [CRAN] It contains an archive of the latest and previous versions of the R distribution, documentation, and contributed R packages. It includes both source packages and pre-compiled binaries for Windows and macOS. As of November 2020, more than 16,000 packages are available.

How do I download and install R?

Installing R on Windows OS.

Go to the CRAN website..

Click on "Download R for Windows"..

Click on "install R for the first time" link to download the R executable [.exe] file..

Run the R executable file to start installation, and allow the app to make changes to your device..

Select the installation language..