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Slogan created by Communists in Indian Subcontinent
Lal Salam (Bengali: লাল সেলাম, Hindi: लाल सलाम, Urdu: لال سلام; transl. "Red salute") is a salute, greeting, or code word used by communists in South Asia. The phrase is a compound of lāl, meaning "red" in Hindi and Urdu, and salām, meaning "peace", a contraction of the Arabic phrase as-salāmu ʿalaykum, a Muslim greeting meaning "peace be upon you".
Further reading
Ali, Kamran Asdar (2015). Surkh Salam: Communist Politics and Class Activism in Pakistan, 1947-1972. Oxford University Press. ISBN978-0-19-940308-0.