R is the eighteenth letter of the modern Latin alphabet. Its name in English ( ) is spelled ar; its name in Hiberno-English is or ( ).

The original Semitic letter was probably inspired by an Egyptian hieroglyph for "head", pronounced t-p in Egyptian, but it was used for /r/ by Semites because in their language, the word for "head" was Rêš (also the name of the letter). It developed into Greek Ρ (Rhô) and Latin R. It is likely that some Etruscan and Western Greek forms of the letter added the extra stroke to distinguish it from a later form of the letter P.

Minuscule

The minuscule (lower-case) form of r developed through several variations on the capital form. 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 today.

Another minuscule, r rotunda, kept the loop-leg stroke but dropped the vertical stroke. It fell out of use around the 18th century.

Various phonetic realizations of R

See rhotic consonant, r-colored vowel, and guttural R for discussion of the family of 'r' sounds.

In the International Phonetic Alphabet, 1 represents the alveolar trill sound. 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 is represents a sound so weak that it is often written interchangeably with w, eg. Kweyol for Kreyol.

Codes for computing

In Unicode the capital R is codepoint U+0052 and the lower case r is U+0072.

The ASCII code for capital R is 82 and for lowercase r is 114; or in binary 01010010 and 01110010, correspondingly.

The EBCDIC code for capital R is 217 and for lowercase r is 153.

The numeric character references in HTML and XML are "R" and "r" for upper and lower case respectively.

Dog's Letter

The letter R is sometimes referred to as the littera canina (canine letter). This phrase has Latin origins: the Latin R was trilled so it sounds like a snarling dog. A good example of a trilling R is 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.

See also

• Р, р - Er (Cyrillic)
• Ρ, ρ or ϱ - Rho (Greek)
• Я, я - (Cyrillic Ya)

• Raidô
• Vocalic r