Red flag

Red flag may refer to:

Red flag (idiom), a metaphor for something signalling a problem
Red flag warning, a term used by meteorologists
Bloody flag, maritime flag signaling an intention to give battle with no quarter (fight to the death)
Red flag (racing), used in auto racing when conditions are too dangerous to continue the session
Red flag (politics), a symbol of socialism, communism or left-wing politics

Politics

Red Flag (magazine), a major political journal published by the Chinese Communist Party
Red Flag Party, a communist party in Venezuela
Peruvian Communist Party (Marxist–Leninist), a communist party in Peru
Red Flag (newspaper), an Australian left-wing newspaper published by Socialist Alternative
Shimbun Akahata (Newspaper Red Flag), the newspaper of the Japanese Communist Party
Red Banner, a symbol of revolutionary struggle used in Russia and the Soviet Union
Flag of the Soviet Union, known as "The Red Banner"

Red flag law, a law that allows the temporary confiscation of firearms from a person deemed a risk to others or to themselves
Red flag traffic laws, laws in the late 19th century affecting drivers of early automobiles
Red Flag Act, properly, Locomotives Act 1865, the 19th-century British road law
Red Flags Rule created by the Federal Trade Commission (FTC) to help prevent identity theft

Exercise Red Flag (also called "Operation Red Flag"), a series of military training exercises
Red Flag – Alaska, a United States Air Force military training exercise conducted in Alaska

The Red Flag, anthem of the British Labour Party
"Red Flag Day", song from U2 album Songs of Experience
Red Flag (Italian song) "Bandiera Rossa", one of the most famous songs of the Italian labour movement
"Red Flag" (song), a song by Billy Talent from Billy Talent II
"Red Flags" (song), a 2023 song by Mimi Webb
"Red Flags", a 2023 song by Josh Ross
"Red Flags", a 2023 song by Plain White T's
The Standard of Revolt (French: Le drapeau rouge), a French socialist song
"Red Flag", a song from Slipknot's album We Are Not Your Kind

A red flag is used by a coach to signal a replay review in gridiron football
Red flags are sometimes used (less often than in the past) on rail transport in Great Britain and Ireland by railway guards as a signal to engine drivers that they must not proceed.
Red Flag 1-class locomotive, a class of electric locomotives used in North Korea.
Red Flag (automobile), or FAW Hongqi, a luxury limousine made by First Automobile Works in China from the late 1950s
Red Flag Linux, the Chinese Linux distribution
Red Flag Publishing House, a book publisher based in China