U1, U.I or U-1 may refer to:

People and characters

Yuvan Shankar Raja Yuvan Shankar Raja (born 31 August 1979), is an Indian composer and playback singer. He mainly scores music for Tamil films along with few Telugu, Kannada, and Hindi films. Considered a versatile composer, he is particularly known for his use o ...

(stage name: U1; born 1979), a Tamil musician and film composer *U-1, a fictional character, the protagonist of the '' Gitaroo Man'' video game

Computing and electronics

*U1, a speed class for Secure Digital (SD) cards * Apple U1, a mobile system-on-a-chip *'' Ultima I: The First Age of Darkness'', a 1981 video game * U1 Technology, a video game publisher

Military

*U-1, the

USAF The United States Air Force (USAF) is the Air force, air service branch of the United States Department of Defense. It is one of the six United States Armed Forces and one of the eight uniformed services of the United States. Tracing its ori ...

and

US Military The United States Armed Forces are the military forces of the United States. U.S. federal law names six armed forces: the Army, Marine Corps, Navy, Air Force, Space Force, and the Coast Guard. Since 1949, all of the armed forces, except th ...

's designation for the

De Havilland Canada DHC-3 Otter The de Havilland Canada DHC-3 Otter is a single-engined, high-wing, Propeller (aircraft), propeller-driven, short take-off and landing (STOL) aircraft developed by de Havilland Canada. It was conceived to be capable of performing the same role ...

light transport aircraft *U-1, Soviet designation for

Avro 504 The Avro 504 is a single-engine biplane bomber made by the Avro, Avro aircraft company and under licence by others. Production during World War I totalled 8,970 and continued for almost 20 years, making it the most-produced aircraft of any kind ...

trainer *Multiple German U-boats named ''U-1'' * Oberursel U.I, an early German aircraft engine * HDMS U-1, a Danish submarine * SM U-1, an Austro-Hungarian submarine, lead ship of the U-1 class

Rail

Locomotives

LNER Class U1 The London and North Eastern Railway Class U1 was a solitary Garratt locomotive designed for banking coal trains over the Worsborough Bank, a steeply graded line in South Yorkshire and part of the Woodhead Route. It was both the longest and ...

, a 1924 British solitary loco *

SR U1 class The SR U1 class were three-cylinder 2-6-0 ('mogul') steam locomotives designed by Richard Maunsell for passenger duties on the Southern Railway. The fifth member of the Maunsell "family" of standardised moguls and 2-6-4 locomotives, the U1 was ...

, a class of 2-6-0 locos

U-Bahn lines

* U1 (Berlin U-Bahn) * U1 (Frankfurt U-Bahn) * U1 (Hamburg U-Bahn) * U1 (Munich U-Bahn) *

U1 (Nuremberg U-Bahn) The U1 is an underground line in Nuremberg U-Bahn, Nuremberg. The first part of the line was opened on 1 March 1972. It is about long and has 27 stations. The termini are Langwasser Süd (Nuremberg U-Bahn), Langwasser Süd in the southeast an ...

U1 (Vienna U-Bahn) Line U1 is a line on the Vienna U-Bahn metro system. Opened in 1978, it currently has 24 stations and a total length of , from to . When the extension to Oberlaa was completed in 2017, the line became the longest on the network, surpassing the ...

Other uses

*U1, unemployment figure released by Bureau of Labor Statistics *U(1), in abstract algebra, the

unitary group Unitary may refer to: Mathematics * Unitary divisor * Unitary element * Unitary group * Unitary matrix * Unitary morphism * Unitary operator * Unitary transformation * Unitary representation * Unitarity (physics) * ''E''-unitary inverse semi ...

of degree one *

U1 spliceosomal RNA U1 spliceosomal RNA is the small nuclear RNA (snRNA) component of U1 snRNP (''small nuclear ribonucleoprotein''), an RNA-protein complex that combines with other snRNPs, unmodified pre-mRNA, and various other proteins to assemble a spliceosome, a ...

, a small nuclear RNA component of the spliceosome involved in pre-mRNA splicing *

UNIONS 1 Ursa Major III / UNIONS 1 (UMa III / U1) is a dwarf satellite galaxy of the Milky Way or a stellar cluster. If confirmed as a galaxy it would represent the smallest and faintest galaxy ever discovered, containing only about 60 star systems as o ...

(U1), a star cluster of the Milky Way Galaxy