U1, U.I or U-1 may refer to:
People Yuvan Shankar Raja (stage name: U1; born 1979), a Tamil musician and film composer
Character 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 and US Military's designation for the De Havilland Canada DHC-3 Otter light transport aircraft U-1, Soviet designation for Avro 504 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, a 1924 British solitary loco SR U1 class, 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) U1 (Vienna U-Bahn)
Other uses U1, unemployment figure released by Bureau of Labor Statistics U(1), in abstract algebra, the unitary group of degree one U1 spliceosomal RNA, a small nuclear RNA component of the spliceosome involved in pre-mRNA splicing UNIONS 1 (U1), a star cluster of the Milky Way Galaxy U1, a definable user mode (like program with preset) on many Nikon DSLRs and MILCs
See also
UI (disambiguation) UL (disambiguation) 1U (disambiguation) 1 (disambiguation) U (disambiguation)
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