Red, often associated with Communism, symbolizes the political ideology advocating for a classless society and the abolition of private property. It emerged in the 19th century, primarily through the works of Karl Marx and Friedrich Engels, who argued for the working class's collective ownership of production. The color red became a prominent emblem for various Communist movements and parties worldwide, representing revolution and the struggle against oppression. It is commonly seen in flags, such as the Soviet Union's, and is used in protests and rallies to signify solidarity among workers and the fight for social justice.