Home › Multilingual Archive Index › R (disambiguation)

R (disambiguation)

R is the eighteenth letter of the Latin alphabet. It may also refer to:

• R (programming language), an environment for statistical computing and graphics
• IBM System R, an IBM database system
• R (complexity), the set of all recursive languages
• R-value (soils), property of soils used in pavement design
• Rated R (album), an album by "Queens of the Stone Age"
• R. (album) (1998) by R. Kelly
• Mundo-R, a Spanish Telecommunications Company
• Rolled-R, the alveolar trill of Spanish, Italian, & Arabic languages
• R-value (insulation), a non-SI measure of thermal resistance used in housing insulation
• The three Rs of Reading, wRiting and aRithmetic
• The three Rs of the Waste hierarchy: of Reduce, Reuse and Recycle
• R (cross section ratio), the ratio of hadronic to muonic cross sections

Chemistry

• In chemistry, the gas constant
• In a chemical formula or structrual formula, an unspecified group of atoms (denoting multiple possibilities exist)

R may also refer to:

• Haplogroup R (mtDNA), a human mitochondrial DNA (mtDNA) haplogroup
• Haplogroup R (Y-DNA), a Y-chromosomal DNA (Y-DNA) haplogroup
• R, a stellar classification, for orangish or K carbon stars
• R, a film rating in the Motion Picture Association of America film rating system
• R, a character played by John Cleese in the James Bond film The World Is Not Enough
• R·Type, an arcade video game
• R with an enclosing circle, ®, denotes a registered trademark
• R, the symbol for the currency of South Africa, the Rand (currency)
• R, the symbol for the amino acid arginine
• R, Japan Radio Company's mobile phone of NTT DoCoMo in Japan

• r, the Pearson product-moment correlation coefficient