R1

R1, R.I., R01 or R-1 may refer to:

Biology

R1 plasmid, a plasmid found in E Coli
ATC code R01 Nasal preparations, a subgroup of the Anatomical Therapeutic Chemical Classification System
Haplogroup R1 (Y-DNA), a human Y-chromosome DNA haplogroup
The R1 vein in insect wings

DeepSeek-R1, an open-source large language model released by DeepSeek in January 2025
R1 (expert system), a 1978 expert system written by John McDermott
.r01, a RAR file extension
an alternate name for the Rice Institute Computer, an innovative computer extant at Rice University from 1959 to 1971

R-1 tank, a Romanian tank from World War II
R-1 (missile), a post World War II Russian rocket
AEG R.I, a 1918 German super-heavy bomber design
DFW R.I, a 1916 German prototype bomber aircraft
HMS Caprice, a destroyer originally designated with Pennant Number R01
Linke-Hofmann R.I, a World War I German prototype bomber aircraft
Polikarpov R-1, a Soviet Union copy of the 1931 British Airco DH.9A light bomber aircraft
USS R-1 (SS-78), a 1918 United States Navy R-class coastal and harbor defense submarine
a South African made version of the FN FAL battle rifle
a version of the 1942 German Rheintochter ground-to-air missile
Sentinel R1, a British airborne radar platform
a Romanian designation of the Czechoslovak-designed tankette AH-IV

R1 (Canberra), a light rail line between Gungahlin and Alinga Street, Australian Capital Territory
R1 (SEPTA), a former commuter rail line in Philadelphia, Pennsylvania, which was split into:
- Airport Line (SEPTA), or R1 Airport line
- SEPTA Main Line (R1 Glenside), also called the Glenside Combined
R1–RG1 (Rodalies de Catalunya), a commuter rail line in Catalonia, Spain
R1 King George Blvd, RapidBus line in Surrey (Metro Vancouver, British Columbia, Canada)
R1 (RER Vaud), an S-Bahn line in the canton of Vaud
Line R1 (Xiamen Metro), China

LCDR R1 class, a class of 0-4-4T steam locomotives built by the South Eastern and Chatham Railway to modified LCDR design in 1900
LNER Class R1, a class of British steam locomotives
PRR R1, a 1934 American single prototype electric locomotive
R1 (New York City Subway car), an American rapid transit multiple-unit
SECR R1 class, a class of 0-6-0T steam locomotives rebuilt by the South Eastern and Chatham Railway from the SER R class between 1910 and 1922

R01 grant, a form of competitive funding issued by the National Institutes of Health in the United States
R1 institution, a level of research activity on the Carnegie Classification of Institutions of Higher Education
R1: Explosive when dry, a risk phrase
R-1 Federation
Rogue One, a 2016 film
R1 Multi-frequency signaling, a telephony control technique
R1 (nuclear reactor), the first nuclear reactor of Sweden
R₁ space in topology, in mathematics
R-1 visa, a non-immigrant visa which allows travel to United States for service as a minister or other religious occupation.
DSC-R1, a 2005 Sony Cyber-shot R series camera
R1, a brand sold by Imperial Tobacco
Region 1, the DVD region code for United States, Canada, Bermuda, U.S. territories
Research I university, a designation of U.S. universities engaged in the highest levels of research activity
BBC Radio 1, a national radio station in the United Kingdom
Radio One (New Zealand) a New Zealand student radio station
Samsung YP-R1, a digital audio player
Rabbit r1, an AI-based personal assistant device
Unitree R1, a humanoid robot developed by Unitree Robotics
DeepSeek R1, a large language model created by DeepSeek